Tomato products and human health
Tomato products are a good source of vitamins C, A and K; potassium, magnesium and fiber. They are also low in calories; a 100-gram serving of canned tomatoes contains only 32 calories. Tomatoes are also high in the carotenoids, beta-carotene and lycopene. 
Lycopene is a powerful antioxidant that gives tomatoes their deep red color and protects against disease. Eating a single serving of tomatoes increases the lycopene level in the bloodstream. When tomatoes are cooked, their lycopene content becomes more available to the body. The body also uses lycopene better when tomato products are prepared with fat such as oil. Scientists believe that it is more than just the isolated lycopene in tomato products offering health benefits. It is the synergy of an array of plant nutrients and compounds working together in the tomato to protect from disease. Eating a regular supply of tomato products has been linked with a reduced rate of chronic diseases.
Eating tomato products has been linked with reduced risks of colorectal, gastric, lung, prostate, and pancreas cancer. The anti-cancer properties in tomatoes seem to be related to their antioxidant levels, particularly from their lycopene, beta-carotene, vitamin C, and phenols. Eating one serving of tomatoes or tomato products every day, but not supplementation with lycopene alone, may help protect against DNA damage that is involved in developing prostate cancer, according to research. Researchers from the UC Davis Health System in Sacramento, CA report that processed tomato products provide sources of lycopene, readily available to the body, that can protect against oxidative damage and cancer-causing effects. The research on tomato products suggests that it is the synergistic effect with lycopene and other nutrients in the tomato that unleashes these positive effects. 
In the most comprehensive scientific analysis of cancer prevention and causation ever undertaken, an expert panel of scientists for the American Institute for Cancer Research reviewed over 4,000 trials, studies, and reports in order to create the organization’s Second Expert Report - Food, Nutrition, Physical Activity, and the Prevention of Cancer: a Global Perspective. The report notes that there is a substantial amount of evidence on tomato products and that food containing lycopene probably does protect against cancer. In particular, foods containing lycopene are cited as providing a convincing decreased risk for prostate cancer.
Tomato products and heart health
Scientists have observed that among people with high levels of lycopene in their bloodstream, there is a tendency for lower rates of cardiovascular disease. This prompted them to investigate the role of lycopene and tomato products on heart disease. In one study, researchers examined data from the Kuopio Ischaemic Heart Disease Risk Factor Study and found that lycopene concentrations in the blood may play a protective role in the early stages of atherosclerosis, a disease characterized by narrowing of the arteries that can disrupt blood flow to the heart or brain. Researchers examining data from the EURAMIC study, which included people from 10 European countries, reported that lycopene may be at the root of the cardio-protective power of a diet rich in vegetables.  Israeli researchers found that a tomato-rich diet increased “good” HDL-cholesterol levels significantly by 15.2 percent.  Daily intake of tomato products, like tomato sauce and tomato juice, may reduce “bad” LDL cholesterol levels by 13 per cent, according to a recent Finnish study published in the British Journal of Nutrition.
Tomatoes contain nutrients that may work in concert to protect lipoproteins and vascular cells from oxidation, the most widely accepted theory for the genesis of atherosclerosis, according to researchers form the Department of Food Science at North Carolina State University. Other heart-protective activities in tomatoes may include the reduction of “bad” LDL cholesterol, homocysteine, platelet aggregation, and blood pressure. 
Tomato products may protect against inflammation, a significant underlying cause of cardiovascular disease, as well as cancer, obesity, metabolic syndrome, type 2 diabetes, osteoporosis, periodontal disease, rheumatoid arthritis, neurological degenerative disorders, and inflammatory bowel disorders. Such were the findings from a recent multi-center, randomized, controlled trial on the effects of processed tomatoes on vasodilatation and C-reactive protein in overweight and obese men and women, presented by one of the study researchers, Rose M Giordano, PhD on 19 April 2009 at the Experimental Biology meeting held in New Orleans, LA. Using data from adults in the National Health and Nutrition Examination Survey (1999 - 2004), the researchers recently found that consumption of processed tomatoes was associated with significantly lower serum C-reactive protein. C-reactive protein is a recognized biomarker of inflammation.
Tomato products are the second highest vegetable dietary contributor of potassium, which helps regulate blood pressure. High blood pressure or hypertension is one of the leading risk factors for heart attack and stroke. The essential mineral, potassium, A low potassium diet can cause high blood pressure. A potassium-rich diet blunts the effects of eating salt on blood pressure. Because potassium and sodium work in opposition to one another, pushing up potassium intake can help flush sodium from the body in order to decrease blood pressure.
- USDA National Nutrient Database for Standard Reference. Accessed on 5 May 2009: http://www.nal.usda.gov/fnic/foodcomp/search/
- Anita Agarwal, Honglei Shen, Sanjiv Agarwal, A.V. Rao. Journal of Medicinal Food. March 2001, 4(1): 9-# Accessed on 5/6/0# http://www.liebertonline.com/doi/abs/10.1089/10966200152053668?cookieSet=1&journalCode=jmf
- Ellinger S, et al. Tomatoes, tomato products and lycopene in the prevention and treatment of prostate cancer: do we have the evidence from intervention studies? Curr Opin Clin Nutr Metab Care. November 2006 ;9(6):722-7.
- Basu, A, et al. Tomatoes versus lycopene in oxidative stress and carcinogenesis: conclusions from clinical trials. Eur J Clin Nutr. 2007 Mar;61(3):295-30#Epub 2006 16 August.
- Second Expert Report - Food, Nutrition, Physical Activity, and the Prevention of Cancer: a Global Perspective Accessed on 5/4/09: http://www.aicr.org/site/PageServer?pagename=res_report_second
- Rissanen TH, et al. Serum lycopene concentrations and carotid atherosclerosis: the Kuopio Ischaemic Heart Disease Risk Factor Study. Am J Clin Nutr. 2003 Jan;77(1):133-9.
- Kohlmeier L, et al. Lycopene and myocardial infarction risk in the EURAMIC Study.Am J Epidemiol. 1997 15 October;146(8):618-26
- Blum A, et al. Effects of tomatoes on the lipid profile. Clin Invest Med. 2006 Oct;29(5):298-300
- Silaste, G, et al. Tomato juice decreases LDL cholesterol levels and increases LDL resistance to oxidation. British Journal of Nutrition December 2007, Volume 98, Issue 6, Pages 1251-1258.
- Willcox JK, et al. Tomatoes and cardiovascular health. Crit Rev Food Sci Nutr. 2003;43(1):1-18.