Meat products contain much more fat and calories than the unrefined plant-based foods thus contributing to obesity by causing leptin resistance. Meat, like fish or dairy, also contain no dietary fiber. And fiber, which is found only in unrefined plant foods, plays very important role in fighting obesity because it absorbs water increasing the volume of food in the stomach without adding calories. In addition, fiber also increases the level of adiponectin thus helping us to control body metabolism and appetite. That is why according to Dr. Dean Ornish the unrefined and rich in fiber plant-based diet should be called the “eat more and weigh less” diet. It means that the less meat is consumed, and the more plant-based products rich in fiber in the diet, the better should be the results.
For example, when you compare, cooked beans or other legumes with the same amount of lean meat you will see that there is not much difference between them as far as calorie content is concerned. Meat would have only about 30% more calories. But, it is fiber that makes difference, because unlike meat, beans contain a lot of fiber which causes that fewer calories from them would be absorbed! The fact that beans, lentils or chick peas are high in dietary fiber, means that they will fill you up faster. That is why beans and other legumes can boost your weight loss efforts. In addition, since legumes contain resistant starch which digests very slowly, you blood sugar level never gets high and therefore, insulin is not released and you won’t get hungry again quickly.
Another problem with meat is that it contains antibiotics which according to some new studies also contribute to obesity. Prof Jan Blustein stated that because for many years farmers have been using antibiotics in order to produce heavier cows for the market, these consumed by people with meat and dairy antibiotics destroy the beneficial bacteria (microflora) present in the gut thus slowing down human metabolism and contributing to overweight. At the same time the antibiotics consumed with meat and dairy significantly weaken human immune system making people more prone to many diseases including cancer.
Studies revealed that people who eat meat on a regular basis have three times the obesity rate of vegetarians and nine times the obesity rate of strict vegetarians who do not consume any animal products. A group of researchers from Cancer Research UK in Oxford compared diets of 22,000 meat eaters and vegetarians. On an average the participants gained about 2 kilos each over a period of five years. However, those who were on plant-based diet gained an average of only 0.5 kilos. Reviewing the results of the study Professor Tim Key said: “Contrary to current popular views that a diet low in carbohydrates and high in protein keeps weight down, we found that the lowest weight gain came in people with high intake of carbohydrate and low intake of protein.” It is estimated that strict vegetarians who do not consume any animal products have, on average, 10 to 20 pounds lower body weight than those who eat meat on a regular basis.
Unfortunately, apart from obesity, meat and all animal products may lead to many other even much more dangerous health problems such as cancer, Creutzfeldt-Jakob disease, leukemia, stroke, heart disease, autoimmune diseases, and many other life-threatening conditions which are triggered by extremely hazardous factors which are found or may be present in meat products. Among the most deadly ones are the following: prions, cancer cells, leukemia virus, cholesterol, triglycerides, dioxins, antibiotics, and many other dangerous factors which are not present in plant foods. Yes, plants may be contaminated with pesticides but according to PETA and other reliable sources meat products contain 15 times as much pesticides as plant foods, and dairy over five times as many! Animal foods contain much more pesticides and other toxins because animals keep absorbing them from plants throughout all their lifetime. This phenomenon is known as the biological magnification. In addition, almost 100% of human exposure to extremely dangerous and carcinogenic dioxins, comes through meat, dairy, and fish consumption.
Drastic reduction in meat consumption always leads to much lower rates of obesity, cancer, cardio-vascular diseases, diabetes and many other diet-related conditions. For example, when in the beginning of World War II Germans invaded Norway and confiscated all the livestock and farm animals to provide food for their own army, Norwegians were forced to switch to a mainly plant-based diet. As a result the whole nation experienced huge improvement in their health status during the war period. The diet-related problems such as the cardiovascular diseases, cancer, or obesity went way down. But as soon as the war was over and Norwegians came back to their normal animal based diet and also again started to consume more refined plant products they quickly became as sick as it was before the war.
Not too many people are aware of the fact that meat products may work as stimulants too. It is so because purines found in animal foods, mainly in meat products, resemble the effect of caffeine. It is believed that both caffeine and all animal foods elevate blood glucose and fat levels, thus increasing the amount of fat stored in the body.
Appleby, P.N. Thorogood, M. Mann, J.I. Key, T.J. (1998). Low body mass index in non-meat eaters: the possible roles of animal fat, dietary fibre and alcohol. International Journal of Obesity Relat Metab Disord. 22:454-60.
Rosell M; Appleby P; Spencer E; Key T (2006). Weight gain over 5 years in 21 966 meat-eating, fish-eating, vegetarian, and vegan men and women in EPIC-Oxford. Int J Obes (Lond); 30 (9):1389-1396.
Cho, Yamanishi, Cox, Methe, Zavadil, Li, Gao, Mahana, Raju, Teitler, Li, Alekseyenko & Blaser. 2012. Antibiotics in early life alter the murine colonic microbiome and adiposity. Nature http://dx.doi.org/10.1038/nature11400
Trasande, Blustein, Liu, Corwin, Cox & Blaser. 2012. Infant antibiotic exposures and early-life body mass. Int J Obesity http://dx.doi.org/10.1038/ijo.2012.132
Sherwood NE, Jeffery RW, French SA, et al. Predictors of weight gain in the Pound of Prevention study. Int J Obes Relat Metab Disord 2000;24(4):395-403.
Astrup A. Macronutreint balances and obesity: the role of diet and physical activity. Public Health Nutr 1999; 2(3A): 341-347.