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'''Juice Plus''' is a branded line of [[dietary supplement]]s containing concentrated fruit and vegetable extracts fortified with added vitamins and nutrients. Juice Plus is manufactured by Natural Alternatives International (NAI; San Marcos, CA) and is distributed by National Safety Associates (NSA; Collierville, TN) through direct or [[multi-level marketing]]. Several Juice Plus products are marketed including '''Orchard Blend''' and '''Garden Blend''' capsules (NSA's main product), '''Vineyard Blend''' capsules, chewable and gummy supplements for children, and a version for dogs and cats.
'''Juice Plus''' is a branded line of encapsulated [[dietary supplement]]s from the [[United States]], which contains concentrated fruit and vegetable extracts fortified with added vitamins and nutrients. Sold via direct or [[multi-level marketing]], it is billed as "the next best thing to fruits and vegetables," a claim which has stirred considerable controversy. Proponents claim that the product can provide nutritional benefits such as reducing [[oxidative stress]], and improving [[cardiovascular]] function. Critics say that there is no scientific proof of serious health benefit, and that Juice Plus makes deceptive claims in its marketing information. Several studies which have set out to prove or disprove Juice Plus's claims have generated conflicting and controversial results.


== Product contents ==
==Product description==
Juice Plus is manufactured by Natural Alternatives International in [[San Marcos, California]] and distributed by National Safety Associates in [[Collierville, Tennessee]] via direct or [[multi-level marketing]]. There are several Juice Plus products, with the primary ones being '''Orchard Blend''' and '''Garden Blend''' capsules, chewable supplements for children, and a version for dogs and cats. <ref name=jphome/>


==Research study results==
===Orchard Blend/Garden Blend===
It is generally accepted in the scientific community that a high intake of fruits and vegetables can result in substantial health benefits, including reduced risk of [[coronary heart disease]] and [[stroke]].<ref name=plotnick/><ref name=samman/> Juice Plus markets itself as a product which can provide some of those benefits in a concentrated form. Multiple studies of varying standards have produced conflicting results as to the truth of these claims.


⚫
===Nutrient absorption===
The Juice Plus Garden Blend U.S. bottle label contains the following information. The recommended daily serving size is 2 capsules (750 mg each), which contain the following [[nutrients]] (as percentages of the [[Reference Daily Intake]]): [[vitamin A]] (as [[beta-carotene]]) 140%, [[calcium]] 4%, [[vitamin E]] 80%, [[vitamin C]] 70%, [[iron]] 2%, and [[folate]] 70%. A 2-capsule serving contains no [[fat]] or [[cholesterol]], 10 mg [[sodium]], 1 g [[carbohydrate]], and less than 1 g each of [[dietary fiber]] and [[protein]]. The ingredients listed in descending order of amount (exact amounts not listed) are: vegetable juice powder and pulp from [[carrots]], [[parsley]], [[beets]], [[kale]], [[broccoli]], [[cabbage]], [[spinach]], and [[tomato]]; [[gelatin]], [[lipase]], [[amylase]], [[protease]], [[cellulase]], beet [[fiber]], barley [[bran]], oat [[bran]], cabbage [[fiber]], [[glucomannan]], plant [[cellulose]], dried plant [[fiber]], ''[[Lactobacillus acidophilus]]'', vegetable-derived [[magnesium stearate]], [[anthocyanins]], [[allicin]], [[lycopene]], polyphenol [[catechins]], ''Dunaliella salina'' ([[algae]]), and [[indole]] [[carbinol]]s.
Though Juice Plus does indeed contain nutrients, concerns have been raised about how many of these nutrients are in a form that can be effectively absorbed by the human body. In studies focusing on the effect of Juice Plus nutrients on human subjects, it was revealed that subjects taking Juice Plus did find high absorption of folate and beta-carotene<ref name=kiefer>{{cite journal | title = Supplementation with mixed fruit and vegetable juice concentrates increased serum antioxidants and folate in healthy adults | author=Kiefer I, Prock P, Lawrence C, Wise J, Bieger W, Bayer P, Rathmanner T, Kunze M, Rieder A | date = 2004 | journal = J Am Coll Nutr | volume=23 | issue=3 | pages= 205-11 | url=http://www.jacn.org/cgi/reprint/23/3/205.pdf | format=pdf}}</ref><ref name=smith>{{cite journal | title = Supplementation with fruit and vegetable extracts may decrease DNA damage in the peripheral lymphocytes of an elderly population | author= Smith MJ, Inserra PF, Watson RR, Wise JA, O'Neill KL | date = 1999 | journal = Nutr Res | volume=19 | issue = 10 | pages= 1507-18}}</ref> <ref name=samman>{{cite journal | author = Samman S., et al. | year = 2003 | title = A mixed fruit and vegetable concentrate increases plasma antioxidant vitamins and folate and lowers plasma homocysteine in men | volume = 133 | issue = 7 | pages = 2188-93 | url = http://jn.nutrition.org/cgi/reprint/133/7/2188 | format = pdf}}</ref> but inconsistent absorption of vitamin E and vitamin C.<ref name=kiefer/><ref name=samman/><ref name=bloomer>{{cite journal | title = Oxidative stress response to aerobic exercise: comparison of antioxidant supplements | author= Bloomer RJ, et al. | date = 2006 | journal = Med Sci Sports Exerc | volume=38 | pages= 1098-1105}}</ref> Other studies found that Juice Plus does not raise the blood levels of other key phytonutrients from fresh fruits and vegetables, such as [[lycopene]],<ref name=smith/><ref name=samman/> [[lutein]],<ref name=smith/><ref name=samman/> [[zeaxanthin]],<ref name=smith/><ref name=samman/><ref name=nantz>{{cite journal | title = Immunity and antioxidant capacity in humans is enhanced by consumption of a dried, encapsulated fruit and vegetable juice concentrate | author= Nantz MP, Rowe CA, Nieves C Jr, Percival SS. | date = 2006 | journal = J Nutr | volume=136 | pages= 2606-10 }}</ref> and beta-cryptoxanthin.<ref name=smith/><ref name=inserra>{{cite journal | author = Inserra PF, Jiang S, Solkoff D, Lee J, Zhang Z, Xu M, Hesslink R, Wise J, Watson RR | year = 1999 | title = Immune function in elderly smokers and nonsmokers improves during supplementation with fruit and vegetable extracts | journal = Integr Med | volume = 2 | issue = 1 | pages = 3-10 }}</ref><ref name=samman/><ref name=nantz/>


⚫
===Antioxidant activity===
The Juice Plus Orchard Blend U.S. bottle label contains the following information. The recommended daily serving size is 2 capsules (750 mg each), which contain the following nutrients (as percentages of the Reference Daily Intake): vitamin A (as beta-carotene) 110%, calcium 2%, vitamin E 70%, vitamin C 320%, iron 2%, and folate 35%. A 2-capsule serving contains no [[fat]] or cholesterol, 5 mg sodium, 1 g carbohydrate (less than 1 g each of dietary fiber and sugars), and less than 1 g protein. The ingredients listed in descending order of amount (exact amounts not listed) are: fruit juice powder and pulp from [[apple]], [[orange (fruit)|orange]], [[pineapple]], [[cranberry]], [[peach]], [[acerola]] cherry, and [[papaya]]; [[gelatin]], [[bromelain]], [[papain]], [[lipase]], [[amylase]], [[protease]], and [[cellulase]]; apple [[pectin]], citrus [[pectin]], date [[fiber]], [[prune (fruit)|prune]] powder, [[glucomannan]], citrus bioflavenoids, dried plant [[fiber]], ''Lactobacillus acidophilus'', vegetable-derived [[magnesium stearate]], [[anthocyanins]], polyphenol [[catechins]], ''Dunaliella salina'' ([[algae]]), and [[indole]] [[carbinol]]s.


NSA claims that the Juice Plus product is an effective antioxidant, and quotes a study, funded by the manufacturer, which showed a 75% reduction in an [[oxidative stress]] marker after 7 to 28 days.<ref name=wise>{{cite journal | title = Changes in plasma carotenoid, alpha-tocopherol, and lipid peroxide levels in response to supplementation with concentrated fruit and vegetable extracts: A pilot study | author= Wise JA, Morin RJ, Sanderson R, Blum K | year = 1996 | journal = Curr Ther Res | volume = 57 | issue = 6 | pages = 445-61| url=http://www.schwebebad-dresden.de/download/ctrstudie.pdf| format=pdf }}</ref> Another independent study in 1999 found a 67% decrease in DNA oxidation,<ref name=smith/> and another independent study also reported reduction in oxidative stress. <ref name=leeds>{{cite journal | title=Availability of micronutrients from dried, encapsulated fruit and vegetable preparations: a study in healthy volunteers | author=Leeds AR, et al. | year = 2000 | journal = J Hum Nutr Diet | volume=13 | pages=21-7 }}</ref> Critics of these studies say that they were poorly designed, not blinded or placebo-controlled, included only a few participants (in one case no more than 15), and did not include monitoring or control of the participants' food intake.<ref name=stanton>{{cite journal | title = Nutrition: who can you believe?| author=Stanton R | date = 2000 | journal = The Skeptic| volume=20 | issue=4 | pages= 23-7 | url = http://www.skeptics.com.au/journal/2000/4_nutrition.pdf}}</ref>
Orchard Blend and Garden Blend are sold only in 4-month supplies of 8 bottles (4 of each). Two capsules per day of each of these products (4 capsules in total) constitute the usual daily regimen. Juice Plus products do not contain [[Organic certification|certified organic]] ingredients. In accordance with the [http://www.fda.gov/opacom/laws/dshea.html| Dietary Supplement Health and Education Act] of 1994,
NSAs distributor manual claims that Juice Plus is not intended to prevent, treat, cure, or mitigate any disease. <ref name=vfom>{{cite book | last = | first = | authorlink = | coauthors = | title = Virtual Franchise Owner's Manual (December 2002) | publisher = National Safety Associates | date = | location = | pages = | url = | doi = | id = }}</ref>


Three other studies which were conducted under more rigorous conditions, meaning [[Randomized controlled trial|randomized]], [[double-blind]], [[placebo]]-controlled studies, longer in duration and with more subjects, found no significant reductions in lipid peroxidation,<ref name=samman/><ref name=kiefer/><ref name=bloomer/> or other markers of oxidative stress.<ref name=samman/><ref name=kiefer/><ref name=nantz/>
Several nutrients, including folate, beta-carotene, vitamin C, and vitamin E, are added to the product’s refined plant powders to compensate for nutrient loss during processing.<ref name=replywatzl>{{cite journal | author = Samman, S. | year = 2003 | title = Letter to the Editor: Reply to Watzl and Bub | journal = J Nutr. | volume = 133 | issue = 7 | pages = 3726 | url = http://jn.nutrition.org/cgi/reprint/133/11/3726 | format = pdf}}</ref> [[Allicin]] and other undisclosed [[phytochemical]]s are also added.<ref name=vfom/> Other additives listed on European bottle labels include thickening and anticaking agents ([[excipients]]), [[calcium carbonate]], [[magnesium carbonate]], [[niacin]], [[vitamin B6]], [[coenzyme Q10]], [[vitamin B1]], and [[vitamin B2]].


⚫
One study on an [[in vitro]] test of [[antioxidant]] activity, found that 1 g of Juice Plus Garden Blend/Orchard Blend powder had the corresponding antioxidant capacity to approximately 10 g (fresh weight) of fruit or vegetable, amounting to 30 g (roughly one-third of a serving) per 4 capsules.<ref name=chambers>{{cite journal | author = Chambers SJ, et al.| year = 1996| title = Evaluation of the antioxidant properties of a methanolic extract from ‘Juice Plus fruit’ and ‘Juice Plus vegetable’ (dietary supplements) | journal = Food Chem | volume = 57 | issue = | pages = 271-274 }}</ref>
⚫
According to the product label, the suggested daily 4-capsule Juice Plus regimen provides (in % [[Reference Daily Intake]] with corresponding amounts in parentheses): folate 105% (420 µg), vitamin C 390% (234 mg), vitamin E 150% (45 IU), beta-carotene 250% (7.5 mg), calcium 6% (61 mg), and iron 4% (0.72 mg). Four studies which included chemical analyses of Juice Plus have indicated nutrient amounts that differ from the amounts listed on the label.<ref Name=plotnick>[http://www.medicalalumni.org/bulletin/spring_2003/faculty.htm Plotnick, Gary]; Corretti MC, Vogel RA, Hesslink, Jr. R, Wise JA. (2003). "[http://www.sciencedirect.com/science?_ob=MImg&_imagekey=B6T18-48MY548-J-3&_cdi=4884&_user=10&_orig=search&_coverDate=05%2F21%2F2003&_qd=1&_sk=999589989&view=c&_alid=467761006&_rdoc=1&wchp=dGLbVlb-zSkzV&md5=72a0609e0af3a33f53575ac5aeaec523&ie=/sdarticle.pdf Effect of supplemental phytonutrients on impairment of the flow-mediated brachial artery vasoactivity after a single high-fat meal]" (pdf). ''J Am Coll Cardiol'' '''41''' (10): 1744-9.</ref>
<ref name=environmental> {{cite news | title=EN Squeezes the Raw Truth Out of Juice Plus Claims | date = March 2002 | publisher= Environmental Nutrition | url = http://www.environmentalnutrition.com/pub/25_3/asken/150372-1.html}}</ref><ref name=Consumerlab> {{cite news | title=Multivitamin/multimineral product review: ingredient comparison tables | date = 2006 | publisher= Consumer Lab}}</ref><ref name=GNLD> {{cite news | title = Are all antioxidants what they claim to be? | date = | publisher= GNLD International | url = http://www.gnld.com.au/downloads/garden_blend_vs_carotenoid.pdf | format = pdf}}</ref> The weight of individual Juice Plus capsules has been variably reported as 1 g,<ref name=chambers>{{cite journal | author = Chambers SJ, et al.| year = 1996| title = Evaluation of the antioxidant properties of a methanolic extract from ‘Juice Plus fruit’ and ‘Juice Plus vegetable’ (dietary supplements) | journal = Food Chem | volume = 57 | issue = | pages = 271-274 }}</ref> 850 mg,<ref name=wise>{{cite journal | title = Changes in plasma carotenoid, alpha-tocopherol, and lipid peroxide levels in response to supplementation with concentrated fruit and vegetable extracts: A pilot study | author= Wise JA, Morin RJ, Sanderson R, Blum K | year = 1996 | journal = Curr Ther Res | volume = 57 | issue = 6 | pages = 445-61| url=http://www.schwebebad-dresden.de/download/ctrstudie.pdf| format=pdf }}</ref><ref name=leeds>{{cite journal | title=Availability of micronutrients from dried, encapsulated fruit and vegetable preparations: a study in healthy volunteers | author=Leeds AR, et al. | year = 2000 | journal = J Hum Nutr Diet | volume=13 | pages=21-7 }}</ref><ref name=kiefer>{{cite journal | title = Supplementation with mixed fruit and vegetable juice concentrates increased serum antioxidants and folate in healthy adults | author=Kiefer I, Prock P, Lawrence C, Wise J, Bieger W, Bayer P, Rathmanner T, Kunze M, Rieder A | date = 2004 | journal = J Am Coll Nutr | volume=23 | issue=3 | pages= 205-11 | url=http://www.jacn.org/cgi/reprint/23/3/205.pdf | format=pdf}}</ref><ref name=smith>{{cite journal | title = Supplementation with fruit and vegetable extracts may decrease DNA damage in the peripheral lymphocytes of an elderly population | author= Smith MJ, Inserra PF, Watson RR, Wise JA, O'Neill KL | date = 1999 | journal = Nutr Res | volume=19 | issue = 10 | pages= 1507-18}}</ref><ref name=inserra>{{cite journal | author = Inserra PF, Jiang S, Solkoff D, Lee J, Zhang Z, Xu M, Hesslink R, Wise J, Watson RR | year = 1999 | title = Immune function in elderly smokers and nonsmokers improves during supplementation with fruit and vegetable extracts | journal = Integr Med | volume = 2 | issue = 1 | pages = 3-10 }}</ref> and 750 mg (current U.S. bottle label), and according to National Safety Associates, the product’s composition has undergone changes since it was first introduced.<ref name=vfom/>
Juice Plus Orchard Blend capsules contain 24.1% concentrated fruit juice powder by weight, and Garden Blend capsules contain 26.3% vegetable juice powder, as listed on UK/Switzerland bottle labels.


⚫
One [[placebo]]-controlled study conducted in 2002 found that Juice Plus Gummie candies did not significantly improve the [[antioxidant]] status of children, as indicated by negative results from 6 different antioxidant tests.<ref name=stewart>{{cite journal | author = Stewart, R.J. et al.| year = 2002 | month=November | title = Antioxidant status of young children: Response to an antioxidant supplement | journal = [[J Am Diet Association]] | volume = 102 | issue = 11 | pages = 1652-7}}</ref> The authors explained this by saying it was possible that the supplement did not contain enough of the proper antioxidants to make a significant difference or that the antioxidants extracted in the fruit/vegetable extract were not [[bioavailable]].
===Gummies===


⚫
===Cardiovascular effects===
Juice Plus gummies consist of 85% [[corn syrup]] and 10% beef [[gelatin]].<ref name=stewart>{{cite journal | author = Stewart, R.J. et al.| year = 2002 | month=November | title = Antioxidant status of young children: Response to an antioxidant supplement | journal = J Am Diet Association | volume = 102 | issue = 11 | pages = 1652-7}}</ref> Chemical analysis during a research study gave the following nutrient amounts based on the recommended daily regimen of 6 gummies (approximate percentage of the adult Reference Daily Intake in parentheses): vitamin C 107.1 mg (179%); vitamin E 82.6 IU (275%); vitamin A 14.8 mg (494%); [[thiamin]] 1.39 mg (93%); [[riboflavin]] 0.05 mg (3%); [[niacin]] 2.51 mg (13%); [[pyridoxine]] 0.64 mg (32%); [[zinc]] 0.62 mg (4%); [[magnesium]] 13.65 mg (3%), calcium 94.5 mg (9%); [[potassium]] 58.4 mg (2%); and [[copper]] 0.32 mg (16%).<ref name=stewart/>
Several studies have examined the effects of fruit and vegetable concentrates on biochemical parameters associated with [[cardiovascular]] function, again with conflicting results.


One non-controlled study found a 37% decrease in [[homocysteine]] levels.<ref name=panunzio>{{cite journal | title = Supplementation with fruit and vegetable concentrate decreases plasma homocysteine levels in a dietary controlled trial | author=Panunzio MF, et al. | date = 2003 | journal = Nutr Res | volume=23 | pages= 1221-8 }}</ref>
⚫
Consumer complaints regarding Juice Plus were received by the [[Better Business Bureau]]'s National Advertising Division (NAD). The NAD said that in April 2005, National Safety Associates advertising featuring Dr. William Sears misleadingly implied that Juice Plus Gummies are low in sugar and are a nutritional alternative to fruits and vegetables. NSA promised to modify its ads and stop calling Gummies “the next best thing to fruits and vegetables”.<ref name=consumerreports>{{cite web | last = | first = | authorlink = | coauthors = | title = How Product Testimonials Bend The Rules | work = | publisher = Consumer Reports | date = | url = http://www.consumerreports.org/cro/personal-finance/producttestimonialtricks-of-the-trade-106.htm | format = | doi = | accessdate = 2006-10-15}}</ref> However, as of 2007, the Juice Plus homepage still features the claim that Juice Plus is “the next best thing to fruits and vegetables”, but not specifically in reference to the Gummies form of the product. <ref name=jphome>{{cite web | last = | first = | authorlink = | coauthors = | title = Juice Plus homepage | work = | publisher = National Safety Associates | date = | url = http://www.juiceplus.com | format = | doi = | accessdate = 2006-10-15}}</ref>


Other more rigorous studies, including two that were [[Randomized controlled trial|randomized]], double-blind, placebo-controlled trials, found that [[homocysteine]] levels were not reduced<ref name=plotnick/><ref name=bamonti>{{cite journal | title=Increased free malondialdehyde concentrations in smokers normalise with a mixed fruit and vegetable juice concentrate: a pilot study | author=Bamonti F, et al. | year=2006 | journal=Clin Chem Lab Med | volume=44 | issue=4 | pages= 391-6 }}</ref> or were reduced only marginally (7%).<ref name=samman/>
== Product research ==
Of the published [[Peer review|peer-reviewed]] studies on Juice Plus products, seven were funded and authored by the manufacturer, NAI,<ref name=plotnick/><ref name=wise/><ref name=leeds/><ref name=kiefer/><ref name=smith/><ref name=inserra/><ref name=samman>{{cite journal | author = Samman S., et al. | year = 2003 | title = A mixed fruit and vegetable concentrate increases plasma antioxidant vitamins and folate and lowers plasma homocysteine in men | volume = 133 | issue = 7 | pages = 2188-93 | url = http://jn.nutrition.org/cgi/reprint/133/7/2188 | format = pdf}}</ref> three were funded by the main distributor, NSA, <ref name=kiefer/><ref name=bloomer>{{cite journal | title = Oxidative stress response to aerobic exercise: comparison of antioxidant supplements | author= Bloomer RJ, et al. | date = 2006 | journal = Med Sci Sports Exerc | volume=38 | pages= 1098-1105}}</ref><ref name=nantz>{{cite journal | title = Immunity and antioxidant capacity in humans is enhanced by consumption of a dried, encapsulated fruit and vegetable juice concentrate | author= Nantz MP, Rowe CA, Nieves C Jr, Percival SS. | date = 2006 | journal = J Nutr | volume=136 | pages= 2606-10 }}</ref> two were funded by individual Juice Plus distributors,<ref name=bamonti>{{cite journal | title=Increased free malondialdehyde concentrations in smokers normalise with a mixed fruit and vegetable juice concentrate: a pilot study | author=Bamonti F, et al. | year=2006 | journal=Clin Chem Lab Med | volume=44 | issue=4 | pages= 391-6 }}</ref><ref name=panunzio>{{cite journal | title = Supplementation with fruit and vegetable concentrate decreases plasma homocysteine levels in a dietary controlled trial | author=Panunzio MF, et al. | date = 2003 | journal = Nutr Res | volume=23 | pages= 1221-8 }}</ref> and two studies were conducted independently.<ref name=chambers/><ref name=stewart/> The products examined in the majority of the studies were Garden Blend and Orchard Blend; one study was performed on Vineyard Blend taken in combination with Garden and Orchard Blend,<ref name=plotnick/> and one study was on Juice Plus Gummies.<ref name=stewart/>


⚫
Two randomized, double-blind placebo controlled studies have examined the effect of Juice Plus on serum cholesterol and [[LDL]] levels. One study found that Juice Plus had no significant effects;<ref name=samman/> the other found slight decreases in cholesterol (6%) and LDL (9%) in subjects that took Orchard/Garden Blend, but no reductions among subjects who took Juice Plus Vineyard blend in addition.<ref name=plotnick/>
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===Nutrient absorption===
Three studies focusing on the uptake of nutrients in the blood of subjects taking Juice Plus found high absorption of folate and beta-carotene<ref name=kiefer/><ref name=smith/><ref name=samman/> and inconsistent absorption of vitamin E and vitamin C.<ref name=kiefer/><ref name=samman/><ref name=bloomer/> Other studies found that Juice Plus does not raise the blood levels of other key phytonutrients from fresh fruits and vegetables, such as [[lycopene]],<ref name=smith/><ref name=samman/> [[lutein]],<ref name=smith/><ref name=samman/> [[zeaxanthin]],<ref name=smith/><ref name=samman/><ref name=nantz/> and beta-cryptoxanthin.<ref name=smith/><ref name=inserra/><ref name=samman/><ref name=nantz/>


One study found that Juice Plus had no effect on [[blood pressure]] in healthy subjects.<ref name=plotnick/>
⚫
===Antioxidant activity===
⚫
Based on an [[in vitro]] test of [[antioxidant]] activity, a study found that 1 g of Juice Plus Garden Blend/Orchard Blend powder had the corresponding antioxidant capacity to approximately 10 g (fresh weight) of fruit or vegetable, amounting to 30 g (roughly one-third of a serving) per 4 capsules.<ref name=chambers/>


⚫
==Juice Plus Children's Research Foundation==
Three studies, which were not blinded or placebo-controlled, found that Juice Plus capsules reduced parameters of [[oxidative stress]].<ref name=smith/><ref name=wise/><ref name=leeds/> One of these studies, authored and sponsored by the manufacturer, reported a 75% reduction in serum lipid peroxides, an [[oxidative stress]] marker, after 7 to 28 days.<ref name=wise/> This study, which has been quoted by NSA in support of the product’s antioxidant efficacy, has been criticized on the basis that it was poorly designed, included only 15 subjects, and failed to include monitoring or control of the participants’ food intake.<ref name=stanton>{{cite journal | title = Nutrition: who can you believe?| author=Stanton R | date = 2000 | journal = The Skeptic| volume=20 | issue=4 | pages= 23-7 | url = http://www.skeptics.com.au/journal/2000/4_nutrition.pdf}}</ref> The results of the study have also been contradicted by three [[Randomized controlled trial|randomized]], [[double-blind]], [[placebo]]-controlled studies, longer in duration and with more subjects, which found no significant reductions in lipid peroxidation,<ref name=samman/><ref name=kiefer/><ref name=bloomer/> or other markers of oxidative stress<ref name=samman/><ref name=kiefer/> in test subjects. The specific oxidation of DNA in subjects taking Juice Plus has been examined in 4 studies. A non-controlled, non-randomized study published in 1999 found a 67% decrease in DNA oxidation;<ref name=smith/>. However, these results were contradicted by three randomized, double-blind, placebo-controlled trials, which found that Juice Plus had no significant effect on DNA oxidation. <ref name=kiefer/><ref name=bloomer/><ref name=nantz/>
The Juice Plus Children's Research Foundation,<ref name=nsajpcrf>{{cite web | last = | first = | authorlink = | coauthors = | title = Juice Plus Children's Research Foundation homepage | work = | publisher = National Safety Associates | date = | url = http://www.childrensresearch.org | format = | doi = | accessdate = 2006-10-15}}</ref> founded in 1997, is a non-profit organization whose stated goal is to initiate and/or support programs that advance the principle that improved nutrition leads to healthier lifestyle and overall better health in children. The foundation is chaired by executives of National Safety Associates and operates from the company's head office in Memphis, Tennessee.


⚫
As of 2007, no research had been published by the Foundation, but it does conduct an ongoing survey which seems to link Juice Plus consumption to a general improvement in diet and lifestyle habits. Critics, including the University of California Berkeley Wellness Letter and Dr. [[Stephen Barrett]] of MLMWatch, question the survey's scientific value, and state that the Foundation is being used mainly as a marketing gimmick to get families to buy Juice Plus products.<ref name=jpcrf>{{cite web | last =Barrett | first = Stephen | authorlink = Stephen Barrett | title =Questionable Research by the Juice Plus Children's Research Foundation | publisher = MLM Watch | date = | url =http://www.mlmwatch.org/04C/NSA/crf.html | accessdate = 2007-02-05}}</ref><ref name=ucbwl2>{{cite web | last = | first = | authorlink = | coauthors = | title = Juiced Up and Dried Out | work = | publisher = University of California Berkeley Wellness Letter | date = | url = http://www.berkeleywellness.com/html/ds/dsJuicePlus.php | format = pdf | doi = | accessdate = 2006-10-15}}</ref>
⚫
A [[placebo]]-controlled study conducted in 2002 found that Juice Plus Gummie candies did not significantly improve the [[antioxidant]] status of children, as indicated by negative results from 6 different antioxidant tests.<ref name=stewart/> The authors said it was possible that the supplement did not contain enough of the proper antioxidants to make a significant difference or that the antioxidants extracted in the fruit/vegetable extract were not [[bioavailable]].


==Marketing claims==
⚫
===Cardiovascular effects===
⚫
According to ''[[Consumer Reports]]'', in 2005, National Safety Associates used advertising featuring Dr. William Sears, which implied that the "Juice Plus Gummies" product is low in sugar, and a nutritional alternative to fruits and vegetables. This claim resulted in consumer complaints to the [[Better Business Bureau]]'s National Advertising Division (NAD). The BBB issued a complaint that NSA's claims were misleading, and as a result, NSA promised to modify its ads and stop calling Gummies “the next best thing to fruits and vegetables”.<ref name=consumerreports>{{cite web | last = | first = | authorlink = | coauthors = | title = How Product Testimonials Bend The Rules | work = | publisher = ''[[Consumer Reports]]'' | date = | url = http://www.consumerreports.org/cro/personal-finance/producttestimonialtricks-of-the-trade-106.htm | format = | doi = | accessdate = 2006-10-15}}</ref> However, as of 2007, the Juice Plus homepage still includes the language that Juice Plus is “the next best thing to fruits and vegetables”, though not specifically in reference to the Gummies form of the product. <ref name=jphome>{{cite web | last = | first = | authorlink = | coauthors = | title = Juice Plus homepage | work = | publisher = National Safety Associates | date = | url = http://www.juiceplus.com | format = | doi = | accessdate = 2006-10-15}}</ref>
⚫
Several studies have examined the effects of Juice Plus on biochemical parameters associated with [[cardiovascular]] function. A non-controlled study found a 37% decrease in [[homocysteine]] levels,<ref name=panunzio/>. Other studies, including two that were [[Randomized controlled trial|randomized]], double-blind, placebo-controlled trials, found that [[homocysteine]] levels were not reduced<ref name=plotnick/><ref name=bamonti/> or were reduced only marginally (7%).<ref name=samman/> Two randomized, double-blind placebo controlled studies have examined the effect of Juice Plus on serum cholesterol and [[LDL]] levels. One study found that Juice Plus had no significant effects<ref name=samman/>; the other found slight decreases in cholesterol (6%) and LDL (9%) in subjects that took Orchard/Garden Blend, but no reductions among subjects who took Juice Plus Vineyard blend in addition.<ref name=plotnick/> One study found that Juice Plus had no effect on [[blood pressure]] in healthy subjects.<ref name=plotnick/>


⚫
Concerns have also been raised about the accuracy of product labeling. Four studies which included chemical analyses of Juice Plus have indicated nutrient amounts that differ from the amounts listed on the product labels.<ref Name=plotnick>[http://www.medicalalumni.org/bulletin/spring_2003/faculty.htm Plotnick, Gary]; Corretti MC, Vogel RA, Hesslink, Jr. R, Wise JA. (2003). "[http://www.sciencedirect.com/science?_ob=MImg&_imagekey=B6T18-48MY548-J-3&_cdi=4884&_user=10&_orig=search&_coverDate=05%2F21%2F2003&_qd=1&_sk=999589989&view=c&_alid=467761006&_rdoc=1&wchp=dGLbVlb-zSkzV&md5=72a0609e0af3a33f53575ac5aeaec523&ie=/sdarticle.pdf Effect of supplemental phytonutrients on impairment of the flow-mediated brachial artery vasoactivity after a single high-fat meal]" (pdf). ''J Am Coll Cardiol'' '''41''' (10): 1744-9.</ref>
===Adverse effects===
<ref name=environmental> {{cite news | title=EN Squeezes the Raw Truth Out of Juice Plus Claims | date = March 2002 | publisher= Environmental Nutrition | url = http://www.environmentalnutrition.com/pub/25_3/asken/150372-1.html}}</ref><ref name=Consumerlab> {{cite news | title=Multivitamin/multimineral product review: ingredient comparison tables | date = 2006 | publisher= Consumer Lab}}</ref><ref name=GNLD> {{cite news | title = Are all antioxidants what they claim to be? | date = | publisher= GNLD International | url = http://www.gnld.com.au/downloads/garden_blend_vs_carotenoid.pdf | format = pdf}}</ref>
The investigators in a study on Garden/Orchard Blend in elderly subjects noted anecdotally that it was generally well tolerated; 2 out of 55 subjects discontinued treatment prematurely and withdrew from the study due to the development of a [[hives|hive]]-like rash.<ref name=inserra/> Another study reported adverse effects (upper-[[respiratory tract]], [[urinary]], and [[musculoskeletal]]) in 5 of 16 subjects who took Juice Plus for 7 days. These events resolved spontaneously and were deemed by the researchers to be unrelated to treatment.<ref name=leeds/> Other [[adverse effect]]s listed in the Juice Plus Franchise Owner's Manual and the Special Nutritional Adverse Event Monitoring System include gastrointestinal [[cramps]], [[fever]], [[nausea]], [[bloating]], [[diarrhea]], and [[constipation]].<ref name=vfom/><ref name=snaems>{{cite web | last = | first = | authorlink = | coauthors = | title = FDA SN/AEMS Web Report | work = | publisher = U.S. Food and Drug Administration | date = 1998-10-20| url = http://www.thememoryhole.org/feds/fda-nutritionals-reports.htm| format = | doi = | accessdate = 2006-10-15}}</ref> Heartburn, abdominal pain, diarrhea, gas with foul odor, and indigestion have been noted as very common risks associated with taking Juice Plus Orchard and Garden Blend, and nausea and vomiting as less common risks;<ref name=IRB>{{cite web | last = | first = | authorlink = | coauthors = | title = CCCWFU #60A02 Protocol Amendment #12 | work = | publisher = Institutional Review Board, Comprehensive Cancer Center of Wake Forest University | date = 2006-19-17| url = http://www1.wfubmc.edu/NR/rdonlyres/778FDC88-D432-415D-BE62-F3726C374086/0/60a022006CRstampedconsentform.pdf | format = | doi = | accessdate = 2007-02-11}}</ref> in some cases these side effects may be serious and long lasting, persisting after use of the supplement has been stopped.


⚫
Doubts have been raised about the benefits of Juice Plus by the [[Memorial Sloan-Kettering Cancer Center]], the [[University of California Berkeley]] and other critics. Specific criticisms include: the product’s marketing being unsupported by research data, the product contains too little fruit and vegetable powder to offer significant clinical benefits, concerns that the effects can be attributed to the inclusion of added [[exogenous]] vitamins and micronutrients, and complaints that the products are excessively priced relative to their potential benefits.<ref name=watzl>{{cite journal | author = Watzl, B. | coauthors=Bub, A. | yeacr = 2003 | title = Letter to the Editor:Fruit and Vegetable Concentrate or Vitamin Supplement? | journal = J Nutr | volume = 133 | issue = 7 | pages = 3725 | url = http://jn.nutrition.org/cgi/reprint/133/11/3725 | format = pdf}}</ref><ref name=mscc>{{cite web | last = | first = | authorlink = | coauthors = | title = Juice Plus| work = | publisher = Memorial Sloan-Kettering Cancer Center | date = | url = http://www.mskcc.org/mskcc/html/11571.cfm?RecordID=637&tab=HC | format = | doi = | accessdate = 2006-10-15}}</ref><ref name=ucbwl1>{{cite web | last = | first = | authorlink = | coauthors = | title = Juice Plus—and minus | work = | publisher = University of California Berkeley Wellness Letter | date = | url = http://www.berkeleywellness.com/subCorner/pdf/2000/0011.pdf | format = pdf | doi = | accessdate = 2006-10-15}}</ref><ref name=ucbwl2/><ref name=goodwin>{{cite web | last = Goodwin | first = Kathy | authorlink = | coauthors = | title = Dietary supplements: facts about Juice Plus | work = | publisher = The Diet Channel | date = | url = http://www.thedietchannel.com/Dietary-Supplements-Facts-About-Juice-Plus.htm | format = | doi = | accessdate = 2006-10-15}}</ref><ref name=stanton/><ref name=mlmw2>{{cite web | last = Barrett| first = Stephen | authorlink = Stephen Barrett| coauthors = | title = Juice Plus: A Critical Look | work = | publisher = MLM Watch| date = | url = http://www.mlmwatch.org/04C/NSA/juiceplus.html | format = | doi = | accessdate = 2006-10-15}}</ref>
⚫
==Juice Plus Children's Research Foundation==
⚫
The Juice Plus Children's Research Foundation,<ref name=nsajpcrf>{{cite web | last = | first = | authorlink = | coauthors = | title = Juice Plus Children's Research Foundation homepage | work = | publisher = National Safety Associates | date = | url = http://www.childrensresearch.org | format = | doi = | accessdate = 2006-10-15}}</ref> founded in 1997, is a non-profit organization whose goal is to initiate and/or support programs that advance the principle that improved nutrition leads to healthier lifestyle and overall better health in children. The foundation is chaired by executives of National Safety Associates and operates from the company's head office in Memphis, TN. As of 2007, no research had been published by the Foundation. The Foundation conducts an ongoing survey which has found a general improvement in diet and lifestyle habits. The scientific value of the survey has been questioned by the University of California Berkeley Wellness Letter and by [[Stephen Barrett]] of MLMWatch, who say that the Foundation is used mainly as a marketing gimmick to get families to buy Juice Plus products.<ref name=jpcrf>{{cite web | last =Barrett | first = Stephen | authorlink = Stephen Barrett | title =Questionable Research by the Juice Plus Children's Research Foundation | publisher = MLM Watch | date = | url =http://www.mlmwatch.org/04C/NSA/crf.html | accessdate = 2007-02-05}}</ref><ref name=ucbwl2>{{cite web | last = | first = | authorlink = | coauthors = | title = Juiced Up and Dried Out | work = | publisher = University of California Berkeley Wellness Letter | date = | url = http://www.berkeleywellness.com/html/ds/dsJuicePlus.php | format = pdf | doi = | accessdate = 2006-10-15}}</ref>

==Criticism and controversy==
⚫
Doubts about the benefits of Juice Plus raised by the Memorial Sloan-Kettering Cancer Center, the University of California Berkeley and other critics include: the product’s marketing being unsupported by research data, the product contains too little fruit and vegetable powder to offer significant clinical benefits, effects can be attributed to the inclusion of added [[exogenous]] vitamins and micronutrients, and the products are excessively priced relative to their potential benefits.<ref name=watzl>{{cite journal | author = Watzl, B. | coauthors=Bub, A. | yeacr = 2003 | title = Letter to the Editor:Fruit and Vegetable Concentrate or Vitamin Supplement? | journal = J Nutr | volume = 133 | issue = 7 | pages = 3725 | url = http://jn.nutrition.org/cgi/reprint/133/11/3725 | format = pdf}}</ref><ref name=mscc>{{cite web | last = | first = | authorlink = | coauthors = | title = Juice Plus| work = | publisher = Memorial Sloan-Kettering Cancer Center | date = | url = http://www.mskcc.org/mskcc/html/11571.cfm?RecordID=637&tab=HC | format = | doi = | accessdate = 2006-10-15}}</ref><ref name=ucbwl1>{{cite web | last = | first = | authorlink = | coauthors = | title = Juice Plus—and minus | work = | publisher = University of California Berkeley Wellness Letter | date = | url = http://www.berkeleywellness.com/subCorner/pdf/2000/0011.pdf | format = pdf | doi = | accessdate = 2006-10-15}}</ref><ref name=ucbwl2><ref name=goodwin>{{cite web | last = Goodwin | first = Kathy | authorlink = | coauthors = | title = Dietary supplements: facts about Juice Plus | work = | publisher = The Diet Channel | date = | url = http://www.thedietchannel.com/Dietary-Supplements-Facts-About-Juice-Plus.htm | format = | doi = | accessdate = 2006-10-15}}</ref><ref name=stanton/><ref name=mlmw2>{{cite web | last = Barrett| first = Stephen | authorlink = Stephen Barrett| coauthors = | title = Juice Plus: A Critical Look | work = | publisher = MLM Watch| date = | url = http://www.mlmwatch.org/04C/NSA/juiceplus.html | format = | doi = | accessdate = 2006-10-15}}</ref>


== References ==
== References ==
{{reflist}}
{{reflist}}



==External links==
* [http://www.juiceplus.com Juice Plus+ homepage]
* [http://www.childrensresearch.org/ Juice Plus Children's Research Foundation]
[[Category:Dietary supplements]]
[[Category:Dietary supplements]]

Revision as of 03:25, 17 February 2007

Juice Plus is a branded line of encapsulated dietary supplements from the United States, which contains concentrated fruit and vegetable extracts fortified with added vitamins and nutrients. Sold via direct or multi-level marketing, it is billed as "the next best thing to fruits and vegetables," a claim which has stirred considerable controversy. Proponents claim that the product can provide nutritional benefits such as reducing oxidative stress, and improving cardiovascular function. Critics say that there is no scientific proof of serious health benefit, and that Juice Plus makes deceptive claims in its marketing information. Several studies which have set out to prove or disprove Juice Plus's claims have generated conflicting and controversial results.

Product description

Juice Plus is manufactured by Natural Alternatives International in San Marcos, California and distributed by National Safety Associates in Collierville, Tennessee via direct or multi-level marketing. There are several Juice Plus products, with the primary ones being Orchard Blend and Garden Blend capsules, chewable supplements for children, and a version for dogs and cats. [1]

Research study results

It is generally accepted in the scientific community that a high intake of fruits and vegetables can result in substantial health benefits, including reduced risk of coronary heart disease and stroke.[2][3] Juice Plus markets itself as a product which can provide some of those benefits in a concentrated form. Multiple studies of varying standards have produced conflicting results as to the truth of these claims.

Nutrient absorption

Though Juice Plus does indeed contain nutrients, concerns have been raised about how many of these nutrients are in a form that can be effectively absorbed by the human body. In studies focusing on the effect of Juice Plus nutrients on human subjects, it was revealed that subjects taking Juice Plus did find high absorption of folate and beta-carotene[4][5] [3] but inconsistent absorption of vitamin E and vitamin C.[4][3][6] Other studies found that Juice Plus does not raise the blood levels of other key phytonutrients from fresh fruits and vegetables, such as lycopene,[5][3] lutein,[5][3] zeaxanthin,[5][3][7] and beta-cryptoxanthin.[5][8][3][7]

Antioxidant activity

NSA claims that the Juice Plus product is an effective antioxidant, and quotes a study, funded by the manufacturer, which showed a 75% reduction in an oxidative stress marker after 7 to 28 days.[9] Another independent study in 1999 found a 67% decrease in DNA oxidation,[5] and another independent study also reported reduction in oxidative stress. [10] Critics of these studies say that they were poorly designed, not blinded or placebo-controlled, included only a few participants (in one case no more than 15), and did not include monitoring or control of the participants' food intake.[11]

Three other studies which were conducted under more rigorous conditions, meaning randomized, double-blind, placebo-controlled studies, longer in duration and with more subjects, found no significant reductions in lipid peroxidation,[3][4][6] or other markers of oxidative stress.[3][4][7]

One study on an in vitro test of antioxidant activity, found that 1 g of Juice Plus Garden Blend/Orchard Blend powder had the corresponding antioxidant capacity to approximately 10 g (fresh weight) of fruit or vegetable, amounting to 30 g (roughly one-third of a serving) per 4 capsules.[12]

One placebo-controlled study conducted in 2002 found that Juice Plus Gummie candies did not significantly improve the antioxidant status of children, as indicated by negative results from 6 different antioxidant tests.[13] The authors explained this by saying it was possible that the supplement did not contain enough of the proper antioxidants to make a significant difference or that the antioxidants extracted in the fruit/vegetable extract were not bioavailable.

Cardiovascular effects

Several studies have examined the effects of fruit and vegetable concentrates on biochemical parameters associated with cardiovascular function, again with conflicting results.

One non-controlled study found a 37% decrease in homocysteine levels.[14]

Other more rigorous studies, including two that were randomized, double-blind, placebo-controlled trials, found that homocysteine levels were not reduced[2][15] or were reduced only marginally (7%).[3]

Two randomized, double-blind placebo controlled studies have examined the effect of Juice Plus on serum cholesterol and LDL levels. One study found that Juice Plus had no significant effects;[3] the other found slight decreases in cholesterol (6%) and LDL (9%) in subjects that took Orchard/Garden Blend, but no reductions among subjects who took Juice Plus Vineyard blend in addition.[2]

One study found that Juice Plus had no effect on blood pressure in healthy subjects.[2]

Juice Plus Children's Research Foundation

The Juice Plus Children's Research Foundation,[16] founded in 1997, is a non-profit organization whose stated goal is to initiate and/or support programs that advance the principle that improved nutrition leads to healthier lifestyle and overall better health in children. The foundation is chaired by executives of National Safety Associates and operates from the company's head office in Memphis, Tennessee.

As of 2007, no research had been published by the Foundation, but it does conduct an ongoing survey which seems to link Juice Plus consumption to a general improvement in diet and lifestyle habits. Critics, including the University of California Berkeley Wellness Letter and Dr. Stephen Barrett of MLMWatch, question the survey's scientific value, and state that the Foundation is being used mainly as a marketing gimmick to get families to buy Juice Plus products.[17][18]

Marketing claims

According to Consumer Reports, in 2005, National Safety Associates used advertising featuring Dr. William Sears, which implied that the "Juice Plus Gummies" product is low in sugar, and a nutritional alternative to fruits and vegetables. This claim resulted in consumer complaints to the Better Business Bureau's National Advertising Division (NAD). The BBB issued a complaint that NSA's claims were misleading, and as a result, NSA promised to modify its ads and stop calling Gummies “the next best thing to fruits and vegetables”.[19] However, as of 2007, the Juice Plus homepage still includes the language that Juice Plus is “the next best thing to fruits and vegetables”, though not specifically in reference to the Gummies form of the product. [1]

Concerns have also been raised about the accuracy of product labeling. Four studies which included chemical analyses of Juice Plus have indicated nutrient amounts that differ from the amounts listed on the product labels.[2] [20][21][22]

Doubts have been raised about the benefits of Juice Plus by the Memorial Sloan-Kettering Cancer Center, the University of California Berkeley and other critics. Specific criticisms include: the product’s marketing being unsupported by research data, the product contains too little fruit and vegetable powder to offer significant clinical benefits, concerns that the effects can be attributed to the inclusion of added exogenous vitamins and micronutrients, and complaints that the products are excessively priced relative to their potential benefits.[23][24][25][18][26][11][27]

References

  1. ^ a b "Juice Plus homepage". National Safety Associates. Retrieved 2006-10-15. {{cite web}}: Cite has empty unknown parameter: |coauthors= (help)
  2. ^ a b c d e Plotnick, Gary; Corretti MC, Vogel RA, Hesslink, Jr. R, Wise JA. (2003). "Effect of supplemental phytonutrients on impairment of the flow-mediated brachial artery vasoactivity after a single high-fat meal" (pdf). J Am Coll Cardiol 41 (10): 1744-9.
  3. ^ a b c d e f g h i j k Samman S.; et al. (2003). "A mixed fruit and vegetable concentrate increases plasma antioxidant vitamins and folate and lowers plasma homocysteine in men" (pdf). 133 (7): 2188–93. {{cite journal}}: Cite journal requires |journal= (help); Explicit use of et al. in: |author= (help)
  4. ^ a b c d Kiefer I, Prock P, Lawrence C, Wise J, Bieger W, Bayer P, Rathmanner T, Kunze M, Rieder A (2004). "Supplementation with mixed fruit and vegetable juice concentrates increased serum antioxidants and folate in healthy adults" (pdf). J Am Coll Nutr. 23 (3): 205–11.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  5. ^ a b c d e f Smith MJ, Inserra PF, Watson RR, Wise JA, O'Neill KL (1999). "Supplementation with fruit and vegetable extracts may decrease DNA damage in the peripheral lymphocytes of an elderly population". Nutr Res. 19 (10): 1507–18.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  6. ^ a b Bloomer RJ; et al. (2006). "Oxidative stress response to aerobic exercise: comparison of antioxidant supplements". Med Sci Sports Exerc. 38: 1098–1105. {{cite journal}}: Explicit use of et al. in: |author= (help)
  7. ^ a b c Nantz MP, Rowe CA, Nieves C Jr, Percival SS. (2006). "Immunity and antioxidant capacity in humans is enhanced by consumption of a dried, encapsulated fruit and vegetable juice concentrate". J Nutr. 136: 2606–10.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  8. ^ Inserra PF, Jiang S, Solkoff D, Lee J, Zhang Z, Xu M, Hesslink R, Wise J, Watson RR (1999). "Immune function in elderly smokers and nonsmokers improves during supplementation with fruit and vegetable extracts". Integr Med. 2 (1): 3–10.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  9. ^ Wise JA, Morin RJ, Sanderson R, Blum K (1996). "Changes in plasma carotenoid, alpha-tocopherol, and lipid peroxide levels in response to supplementation with concentrated fruit and vegetable extracts: A pilot study" (pdf). Curr Ther Res. 57 (6): 445–61.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  10. ^ Leeds AR; et al. (2000). "Availability of micronutrients from dried, encapsulated fruit and vegetable preparations: a study in healthy volunteers". J Hum Nutr Diet. 13: 21–7. {{cite journal}}: Explicit use of et al. in: |author= (help)
  11. ^ a b Stanton R (2000). "Nutrition: who can you believe?" (PDF). The Skeptic. 20 (4): 23–7.
  12. ^ Chambers SJ; et al. (1996). "Evaluation of the antioxidant properties of a methanolic extract from 'Juice Plus fruit' and 'Juice Plus vegetable' (dietary supplements)". Food Chem. 57: 271–274. {{cite journal}}: Explicit use of et al. in: |author= (help)
  13. ^ Stewart, R.J.; et al. (2002). "Antioxidant status of young children: Response to an antioxidant supplement". J Am Diet Association. 102 (11): 1652–7. {{cite journal}}: Explicit use of et al. in: |author= (help); Unknown parameter |month= ignored (help)
  14. ^ Panunzio MF; et al. (2003). "Supplementation with fruit and vegetable concentrate decreases plasma homocysteine levels in a dietary controlled trial". Nutr Res. 23: 1221–8. {{cite journal}}: Explicit use of et al. in: |author= (help)
  15. ^ Bamonti F; et al. (2006). "Increased free malondialdehyde concentrations in smokers normalise with a mixed fruit and vegetable juice concentrate: a pilot study". Clin Chem Lab Med. 44 (4): 391–6. {{cite journal}}: Explicit use of et al. in: |author= (help)
  16. ^ "Juice Plus Children's Research Foundation homepage". National Safety Associates. Retrieved 2006-10-15. {{cite web}}: Cite has empty unknown parameter: |coauthors= (help)
  17. ^ Barrett, Stephen. "Questionable Research by the Juice Plus Children's Research Foundation". MLM Watch. Retrieved 2007-02-05.
  18. ^ a b "Juiced Up and Dried Out" (pdf). University of California Berkeley Wellness Letter. Retrieved 2006-10-15. {{cite web}}: Cite has empty unknown parameter: |coauthors= (help)
  19. ^ "How Product Testimonials Bend The Rules". Consumer Reports. Retrieved 2006-10-15. {{cite web}}: Cite has empty unknown parameter: |coauthors= (help); Italic or bold markup not allowed in: |publisher= (help)
  20. ^ "EN Squeezes the Raw Truth Out of Juice Plus Claims". Environmental Nutrition. March 2002.
  21. ^ "Multivitamin/multimineral product review: ingredient comparison tables". Consumer Lab. 2006.
  22. ^ "Are all antioxidants what they claim to be?" (pdf). GNLD International.
  23. ^ Watzl, B. "Letter to the Editor:Fruit and Vegetable Concentrate or Vitamin Supplement?" (pdf). J Nutr. 133 (7): 3725. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |yeacr= ignored (help)
  24. ^ "Juice Plus". Memorial Sloan-Kettering Cancer Center. Retrieved 2006-10-15. {{cite web}}: Cite has empty unknown parameter: |coauthors= (help)
  25. ^ "Juice Plus—and minus" (pdf). University of California Berkeley Wellness Letter. Retrieved 2006-10-15. {{cite web}}: Cite has empty unknown parameter: |coauthors= (help)
  26. ^ Goodwin, Kathy. "Dietary supplements: facts about Juice Plus". The Diet Channel. Retrieved 2006-10-15. {{cite web}}: Cite has empty unknown parameter: |coauthors= (help)
  27. ^ Barrett, Stephen. "Juice Plus: A Critical Look". MLM Watch. Retrieved 2006-10-15. {{cite web}}: Cite has empty unknown parameter: |coauthors= (help)
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