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Five Major Poisons Inherently Found in Animal Foods

Updated February 18, 2022

By John McDougall, MD

Protein, fat, cholesterol, methionine (a sulfur-containing amino acid), and dietary acids, which are all superabundant in animal foods, are poisoning nearly everyone following the standard Western diet. Most people cannot fathom this, because it takes four or more decades of consumption before disability, disfigurement, and death become common from these endogenous toxins. This long latent period fools the public into thinking there is no harm done by choosing an animal-food-based diet. If the case were one of instantaneous feedback—one plate of fried eggs caused excruciating chest pains, paralysis from a stroke following a prime rib dinner, or a hard cancerous lump appeared within a week of a grilled cheese sandwich—then eating animal foods would be widely recognized as an exceedingly unwise choice. Similar failures to appreciate slow poisonings from our lifestyle choices are seen with tobacco and alcohol use. If one package of cigarettes were followed by a week on a respirator or a bottle or two of gin caused hepatic (liver) coma then no one would indulge in these instruments of long-drawn-out death either. The difference defining the failure to take long overdue actions is that the dangers from tobacco and alcohol use are universally known and accepted, whereas almost everyone considers red meat, poultry, eggs, and dairy products necessary parts of a healthy diet. 

The Art of Selling Slow Poisons: Distract the Consumer

Sellers of animal foods for human consumption draw in customers with the marketing strategy of “unique positioning”—each industry tries to make its merchandise stand apart from other foods by promoting a nutrient that is especially plentiful in its product. Over time this effective advertising approach has meant that the mention of calcium brings to mind milk and cheese, iron has become synonymous with beef, and eggs are well known as the “best source of high-quality protein.” 

Because these highly sensationalized nutrients are always plentiful in basic plant foods, illnesses from deficiencies of these nutrients are essentially unknown, as long as there is enough food to eat. Thus, there are no real nutritional advantages to choosing red meat, poultry, dairy, and egg products with an especially high density of one particular nutrient. Ironically, milk and cheese are iron deficient, and red meat, poultry, and eggs (unless you eat the shells) contain almost no calcium. 

Focusing on the abundance of an individual nutrient accomplishes an even more insidious marketing goal; it diverts the consumer’s, and oftentimes the professional dietitian’s, attention away from the harmful impact on the human body of consuming all kinds of animal foods. In my 42-years of providing medical care I have never seen a patient sickened by eating potatoes, sweet potatoes, corn, rice, beans, fruits, and/or vegetables (unspoiled and uncontaminated). However, during my everyday practice I have witnessed (just like every other practicing medical doctor has) a wide diversity of diseases, including heart attacks, strokes, type-2 diabetes, arthritis, osteoporosis, and cancer, from eating fresh-killed and/or collected, as well as processed and/or preserved, animal-derived foods.

A Simplified View of Animal-food Poisoning

Animal foods—be they from cow, pig, or chicken muscles or the ovum of a bird or the lactation fluids of a mammal—are all so similar in their nutritional makeup and their impact on human health that they should be considered as the same (see the comparison tables at the end of this article). In order to avoid the confusion created by the marketing strategy of “unique positioning,” let’s look at different kinds of animal products mixed together to make one food; and compare them to their antithesis, starches. 

If I were to blend together red meat, chicken, eggs, and cheese, which most Americans do three or more times a day in their stomachs, the end product would be a highly acidic mixture of mostly protein, fat, and water—each individual food having contributed a similar amount of each component. A blend of various starches—beans, rice, potatoes, and sweet potatoes—would produce an opposite in composition.

Protein, fat, cholesterol, methionine (a sulfur-containing amino acid), and dietary acids, which are all superabundant in animal foods, are poisoning nearly everyone following the standard Western diet. Most people cannot fathom this, because it takes four or more decades of consumption before disability, disfigurement, and death become common from these endogenous toxins. This long latent period fools the public into thinking there is no harm done by choosing an animal-food-based diet. If the case were one of instantaneous feedback—one plate of fried eggs caused excruciating chest pains, paralysis from a stroke following a prime rib dinner, or a hard cancerous lump appeared within a week of a grilled cheese sandwich—then eating animal foods would be widely recognized as an exceedingly unwise choice. Similar failures to appreciate slow poisonings from our lifestyle choices are seen with tobacco and alcohol use. If one package of cigarettes were followed by a week on a respirator or a bottle or two of gin caused hepatic (liver) coma then no one would indulge in these instruments of long-drawn-out death either. The difference defining the failure to take long overdue actions is that the dangers from tobacco and alcohol use are universally known and accepted, whereas almost everyone considers red meat, poultry, eggs, and dairy products necessary parts of a healthy diet. 

A Comparison of a Blend of Animals vs Starches
  Animal Food Starches Comparisons
Protein 35 13 3 Times
Fat 61 4 15 Times
Cholesterol 92 0 >100 times
Methionine 254 64 4 Times
Acid (RAL)  8 <1 >10 times
*Figures for protein and fat are in percent of calories. Figures for cholesterol and methionine are in milligrams (mg) per 100 calories. Dietary acid (a calculation called the renal acid load—RAL) is per 100 calories.

Charts at the end of this article are the source for these comparisons.

The Five Overloads from Animal Foods that Poison Us

Protein, fat, cholesterol, sulfur-containing amino acids (methionine, for example), and dietary acids poison us when consumed in amounts that exceed the body’s metabolic capabilities to detoxify and eliminate the excesses. Compared to the proper human diet, which is based on starches (see my February 2009 newsletter), animal foods burden us with three times more protein, fifteen times more fat, greater than 100 times more cholesterol, four times more methionine, and at least ten times more dietary acid. Furthermore, the toxic effects of these poisons are interactive. For example, excesses of protein, methionine, and dietary acids work together to destroy the bones. Excesses of dietary fat and cholesterol combine their deleterious effects to damage the arteries (atherosclerosis) and promote cancer. Let me provide some more details on how these five destructive elements from animal foods ruin your health.

Protein Overload 

Once your protein needs are met then the excess must be eliminated from your body, primarily by your liver and kidneys. You can notice an overload of protein by the strong smell of urea in your body sweat and urine. The work of eliminating excess protein takes a toll even on healthy people. On average, 25% of kidney function is lost over a lifetime (70 years) from consuming the high animal-protein Western diet.1,2 For people with already damaged livers and kidneys, consuming excess protein will speed up the processes that lead to complete organ failure.3-7 Excess protein damages the bones. Doubling the dietary intake of protein increases the loss of calcium into the urine by 50%, fostering the development of osteoporosis and kidney stones.8

Lipotoxicity (Fat Overload)

The most recent report (for 2007 to 2008) on the epidemic of obesity in the US finds 33.8% of adults obese with 68.0% of all adults overweight.9 Dietary fats are almost effortlessly stored in your body fat.10 When consumed in excess, dietary fats also result in a surplus of fats stored in your liver, heart, and muscles. From all this over-accumulation, insulin resistance develops, contributing to other health problems, including heart disease, strokes, and type-2 diabetes.11 The extra pounds you carry around cause damage to the joints of your lower extremities (osteoarthritis). Excess fat in your diet and on your body alters your cellular metabolism, promoting cancers by many already discovered mechanisms.12

Cholesterol Overload

Cholesterol is only found in animal products. As an animal, you make all the cholesterol you need. Unfortunately, your capacity to eliminate it is limited to a little more than the amount you make. As a result, the cholesterol added by eating animal foods accumulates in your body parts, including your skin, tendons, and arteries. Cholesterol deposited in your arteries is a major contributor to vascular diseases of your heart and brain.13 Cholesterol also facilitates cancer development.14

Sulfur Toxicity

Overconsumption of sulfur-containing amino acids (for example, methionine) will cause you many unwelcome problems.15 Most noticeably, sulfur stinks, like rotten eggs, causing halitosis, body odor, and noxious flatus. Methionine is metabolized into homocysteine, a risk factor for heart attacks, strokes, peripheral vascular disease, venous thrombosis, dementia, Alzheimer’s disease, and depression. Sulfur feeds cancerous tumors and is known to be toxic to the tissues of the intestine. Sulfur-containing amino acids are metabolized into sulfuric acid—one of the most potent acids found in nature.

Acid Overload

After ingestion, your body must neutralize the over-abundance of endogenous dietary acids in the animal foods you eat. Your bones are the primary buffering system of your body.16-20 They counteract these dietary acids by releasing alkaline materials (carbonate, citrate, and sodium)—thereby the bones dissolve. Acids from animal foods also raise cortisol (steroid) levels in your body.21 An excess of steroid is another mechanism for further bone loss. The net result from this chronic acid poisoning is kidney stones and osteoporosis.

Detoxifying with a Starch-based Diet

Simply by making the right food choices you will immediately relieve yourself from the burden of five dietary poisons inherently found in animal foods. At the same time you will be reducing your intake of pesticides, antibiotics, and other toxic chemicals found in high concentrations in most animal foods. You will also be adding generous amounts of complex carbohydrates, dietary fibers, alkaline substances, and a healthy balance of vitamins, minerals, and essential phyto-chemicals to your body. And finally, you will be avoiding exposure to animal-borne, infectious microbes (bacteria, viruses, parasites, and prions) that can cause acute and deadly illnesses. Give yourself a break today: choose starches, free of the five endogenous poisons superabundant in animal foods.

Animal Foods Means Calories from Fat and Protein
  Beef Chicken Cheese Egg Blended Together
Protein 37 46 25 32 35
Fat 57 51 74 61 61
Cholesterol 32 36 26 272 92
Acid (RAL) 6.3 7.0 10 8.2 8
Plant Foods Means Calories from Carbohydrates
  Beans Rice Potato Sweet Potato Blended 

Together

Protein 29 9 8 7 13
Fat 4 8 1 1 4
Cholesterol 0 0 0 0 0
Acid (RAL) 1 1 -5 -9 -3
Figures for protein and fat are in percent of calories. Figures for cholesterol and methionine are in milligrams (mg) per 100 calories. Dietary acid (a calculation called the renal acid load—RAL) is per 100 calories.

References:

Calculations based on information found in: Pennington J. Food Values of Portions Commonly Used—17th edition. Lippincott.

1) Brenner BM. Dietary protein intake and the progressive nature of kidney disease: the role of hemodynamically mediated glomerular injury in the pathogenesis of progressive glomerular sclerosis in aging, renal ablation, and intrinsic renal disease. N Engl J Med. 1982 Sep 9; 307(11): 652-9.

2) Meyer TW. Dietary protein intake and progressive glomerular sclerosis: the role of capillary hypertension and hyperperfusion in the progression of renal disease. Ann Intern Med. 1983 May; 98(5 Pt 2): 832-8.

3) Hansen HP. Effect of dietary protein restriction on prognosis in patients with diabetic nephropathy. Kidney Int. 2002 Jul; 62(1): 220-8.

4) Biesenbach G. Effect of mild dietary protein restriction on urinary protein excretion in patients with renal transplant fibrosis. Wien Med Wochenschr. 1996; 146(4): 75-8.

5) Pedrini MT. The effect of dietary protein restriction on the progression of diabetic and nondiabetic renal diseases: a meta-analysis. Ann Intern Med. 1996 Apr 1;124(7):627-32.

6) Cupisti A. Vegetarian diet alternated with conventional low-protein diet for patients with chronic renal failure. J Ren Nutr. 2002 Jan;12(1):32-7.

7) Bianchi GP. Vegetable versus animal protein diet in cirrhotic patients with chronic encephalopathy. A randomized cross-over comparison. J Intern Med. 1993 May; 233(5): 385-92.

8) Hegsted M, Schuette SA, Zemel MB, Linkswiler HM. Urinary calcium and calcium balance in young men as affected by level of protein and phosphorus intake. J Nutr. 1981 Mar;111(3):553-62.

9) Flegal KM, Carroll MD, Ogden CL, Curtin LR. Prevalence and trends in obesity among US adults, 1999-2008. JAMA. 2010 Jan 20;303(3):235-41. 

10) Danforth E Jr. Diet and obesity. Am J Clin Nutr. 1985 May;41(5 Suppl):1132-45.

11) Schrauwen P. High-fat diet, muscular lipotoxicity and insulin resistance. Proc Nutr Soc. 2007 Feb;66(1):33-41.

12) Yecies JL, Manning BD. Chewing the fat on tumor cell metabolism. Cell. 2010 Jan 8;140(1):28-30.

13) Subramanian S, Chait A. The effect of dietary cholesterol on macrophage accumulation in adipose tissue: implications for systemic inflammation and atherosclerosis. Curr Opin Lipidol. 2009 Feb;20(1):39-44. 

14) Morin RJ, Hu B, Peng SK, Sevanian A. Cholesterol oxides and carcinogenesis. J Clin Lab Anal. 1991;5(3):219-25. 

15) The March 2005 McDougall Newsletter.

16) Remer T. Influence of diet on acid-base balance. Semin Dial. 2000 Jul-Aug;13(4):221-6.

17) Frassetto L.Diet, evolution and aging–the pathophysiologic effects of the post-agricultural inversion of the potassium-to-sodium and base-to-chloride ratios in the human diet. Eur J Nutr. 2001 Oct;40(5):200-13.

18) Remer T. Potential renal acid load of foods and its influence on urine pH. J Am Diet Assoc. 1995 Jul;95(7):791-7.

19) Barzel US. Excess dietary protein can adversely affect bone. J Nutr. 1998 Jun;128(6):1051-3.

20) Jajoo R, Song L, Rasmussen H, Harris SS, Dawson-Hughes B. Dietary acid-base balance, bone resorption, and calcium excretion. J Am Coll Nutr. 2006 Jun;25(3):224-30. 

21)Maurer M. Neutralization of Western diet inhibits bone resorption independently of K intake and reduces cortisol secretion in humans. Am J Physiol Renal Physiol. 2003 Jan; 284(1): F32-40.