Nathan Pritikin

What Nathan says, topic by topic

Vitamin B12

In a 1982 recorded conversation with John McDougall, Pritikin said that after years with no animal protein he began adding small amounts back, chiefly because he could not see another way to get vitamin B12¹. He said he settled on about one microgram a day, the minimum he had worked out for himself¹.

What all the experts say about vitamin B12

Oil

In the same 1982 conversation Pritikin cited a National Cancer Institute statement from a few months earlier as naming the amount of dietary fat as the main cause of breast, colon and prostate cancer². He added that polyunsaturated oils such as corn, safflower and sunflower oil doubled colon cancer risk, and said the American Heart Association, which recommended those oils, would have to change its advice².

What all the experts say about oil

Protein

Pritikin told McDougall that anyone eating enough calories to keep their weight cannot fall short of protein, and that even a trained dietitian would struggle to design a diet that low³. He rejected calling plant proteins “incomplete”, saying every one analyzed holds all the amino acids, and named gelatin and egg white as proteins that lack some⁴.

He cited a Purdue study in which young men met their needs on white rice giving 6% of calories as protein, and said his own diet supplied about 13%, twice the need⁵. He called the protein combining advice of the book Diet for a Small Planet unscientific and said it had done more harm than good⁶.

What all the experts say about protein

Calcium, dairy and bones

In 1982 Pritikin described dairy foods as unnatural for humans and said his program kept a little only to avoid putting the whole world off⁷. The dairy it allowed was nonfat, such as skim milk and skim cheese, and he put lactose intolerance at about a quarter of white adults and three quarters of black adults in the West⁸.

He said calcium deficiency was not a concern, recounting that a World Health Organization search had found no case of it in the medical literature⁹. In his view protein above about 16% of calories causes a net loss of calcium in the urine, which he called the main cause of osteoporosis, even with plenty of milk¹⁰.

What all the experts say about calcium, dairy and bones

Salt

Pritikin said people get used to unsalted food in about two weeks, put up with it for roughly another month, and after that prefer it¹¹. Late in the 1982 conversation he welcomed a recent announcement by large canning companies that they would stop adding salt to canned vegetables¹².

What all the experts say about salt

Starches

Pritikin recalled that after his heart disease diagnosis he changed to whole grains, beans and peas, fruits, vegetables and potatoes, and at first cut out all animal protein and dairy to lower his cholesterol quickly¹³. Describing his program’s food in 1982, he listed pasta dishes, brown rice, corn tortillas and other grains such as millet, and agreed that starches, vegetables and fruits make the diet that best supports health¹⁴.

What all the experts say about starches

Fish and eggs

Pritikin said that once his cholesterol had held near 100 for years, he tested himself by eating three quarters of a pound daily of chicken or fish for six weeks, and his cholesterol stayed at 105 to 108¹⁵. His 1982 program allowed small portions of light chicken, low-fat fish and lean beef; he preferred grass-fed beef to feedlot cattle, which he described as very fatty¹⁶.

He saw no real benefit in these animal foods beyond making the diet feel closer to people’s old habits, and said patients lost their taste for beef and came to use fish or poultry as a condiment rather than the center of the plate¹⁷.

What all the experts say about fish and eggs

Fiber

Pritikin called his diet the best one for colon problems, naming diverticulosis, Crohn’s disease, ulcerative colitis and hemorrhoids, and argued that the low-fiber diets used to treat them are what cause them¹⁸. He said constipation clears up on it as well¹⁸.

What all the experts say about fiber

Whole grains, bread and flour

The diet Pritikin adopted after his diagnosis was built on whole grains along with beans, peas, fruits, vegetables and potatoes¹³. In 1982 he said his program’s whole-grain menu ran from spaghetti, lasagna and pizza made to its own recipes to brown rice dishes, corn tortillas and millet, and that any foreign cuisine could be adapted to it¹⁴. Citing a study in which young men met their protein needs on plain white rice, he stressed that he would recommend white rice to nobody, since it lacks vitamins, minerals and fiber⁵.

What all the experts say about whole grains, bread and flour

Meat

Pritikin told McDougall in 1982 that his cholesterol took three years without animal protein to reach 100, and that when he began eating some animal protein again it climbed to 140 within a month¹⁹. Only after a further spell without it, and then small weekly amounts that left his cholesterol at 100, did he try larger daily servings of chicken or fish¹⁵.

His program allowed a little lean meat. Beef had to be grass-fed or range-fed, at most a small piece of flank steak, and he rejected feedlot cattle, which he put at about 70% of calories from fat¹⁶. He said the meat brought no real advantage beyond making the diet feel familiar, and that patients tended to lose their taste for beef and kept fish or poultry only as a side flavoring¹⁷.

What all the experts say about meat

Low-fat eating

In 1982 Pritikin traced his ideas to wartime health data. He said that in England and Wales deaths from heart disease and from diabetes fell by half by 1944, and that after the war only the countries that had sharply restricted fat and cholesterol, not calories, saw heart deaths drop, while those without such limits saw them rise²⁰.

He then studied 25 populations with the lowest fat and cholesterol intake in the world and said heart attacks were practically unknown there, as were diabetes, hypertension, breast, colon and prostate cancer, arthritis and glaucoma²¹. He also cited the National Cancer Institute as naming dietary fat as the main cause of three common cancers².

What all the experts say about low-fat eating

Cholesterol

Pritikin recalled that by the early 1950s his own cholesterol was around 300, yet his doctors called it high normal and told him not to worry²². On his new diet it fell to 100 after three years, rose to 140 within a month when he reintroduced animal protein, and returned to 100 once he stopped again¹⁹. A later six-week test with daily chicken or fish left it at 105 to 108, which he took to mean his body had cleared its stored excess¹⁵.

He also linked gallstones to cholesterol. In 1982 he said the gallstones of developed populations are cholesterol stones, that removing cholesterol from the diet dissolves them in animal studies, and that his program had seen two cases where they disappeared²³.

What all the experts say about cholesterol

Carbohydrates and low-carb diets

Pritikin held that a high-carbohydrate diet of natural foods gives more endurance than any other. To show that his diet was not only for sick people, he said in 1982 that he had sponsored six athletes in the October 1982 Ironman triathlon at Kona, and that they took the first four places among some 850 entrants²⁴.

What all the experts say about carbohydrates and low-carb diets

Coffee, tea and caffeine

In 1982 Pritikin said caffeine was linked with fibrocystic breast disease in women and with ulcers in both sexes, because regular and decaffeinated coffee alike strongly raise stomach acid; in his view it should not be drunk as a beverage²⁵. He added that people with high blood pressure should avoid both caffeine and alcohol, since studies showed each raises blood pressure²⁶.

What all the experts say about coffee, tea and caffeine

Alcohol

Pritikin told McDougall in 1982 that he had no serious objection to one drink a day for people with no symptoms and no medication. He noted that beer had been tied to colon cancer in men and might affect breast cancer risk in women, while saying the facts were not yet in, and he insisted that “alcohol is a drug” rather than a food²⁷. He said people with high blood pressure should not drink it²⁶.

What all the experts say about alcohol

Cravings and food addiction

Asked in 1982 why health groups did not support dietary change, Pritikin said he preferred to believe people were honest and suggested the reason might simply be that eating habits are entrenched and addictive, the hardest kind of habit to break²⁸. He described the taste for foods such as dairy as something learned, trained in the same way as a taste for cigarettes²⁹.

What all the experts say about cravings and food addiction

Exercise

Pritikin recalled that after his 1955 diagnosis his cardiologist limited him to four blocks of walking a day, with a daily nap and medication³⁰. Once his cholesterol reached 100 he felt safe to build up his exercise over six to eight years, until he was running seven or eight miles at a time³¹.

In 1982 he said brisk walking for an hour a day, or split into two or three shorter walks, is all a person needs to stay fit for life; jogging was fine for extra endurance, and he and his wife ran five to ten miles most days³². Answering a Rhode Island study linking jogging with a sevenfold rise in heart deaths, he said the risk applied to people on the American diet, and pointed to the Tarahumara of northern Mexico, who run very long races on a diet like his with no heart disease found since 1910³³.

For patients his center prescribed only mild walking, built up gradually; it discouraged running for heart patients, since a lapse back to the old diet could be dangerous, and asked for moderation in weightlifting³⁴. He said the aerobic part of exercise is what matters for the heart, and that stop-and-go tennis was fine only for people who also walked an hour a day³⁵.

What all the experts say about exercise

Heart disease

In 1982 Pritikin said that wartime data, not stress, shaped his view of heart disease: deaths fell where fat and cholesterol were scarce²⁰, and in Austria in 1958, at a time of full employment and little stress, the heart death rate was seven times its 1944 level³⁶.

He said he was diagnosed with serious coronary insufficiency in 1955, at age 40, and saw a dozen cardiologists who all confirmed it³⁷. By 1966, after years on his diet and a slow build-up of exercise, he ran on a treadmill at 8.5 miles an hour for 20 minutes with no abnormal beat, and said “I knew I was cured”³¹.

He described a five-month controlled study of 19 patients and 19 controls at the Long Beach VA hospital, presented in 1975, which he said showed on angiograms a reversal of narrowing in leg arteries, besides relief of heart symptoms³⁸. At his center, he said, patients whose bypass grafts had closed, some after as many as four operations, regained enough circulation to stop all medication and lead normal lives³⁹.

What all the experts say about heart disease

High blood pressure

Pritikin said in 1982 that 85% of the hypertensive patients who came to his center on medication left it with normal blood pressure within four weeks, some after 20 years of pills⁴⁰. He listed side effects he attributed to the drugs: a push toward diabetes, occasional kidney failure, gout from raised uric acid, and loss of potency in half of men within two years⁴¹.

He criticized official advice to keep 75 million Americans on lifelong drugs, extended even to small children in the upper normal range⁴². He said he would back the drugs himself if they were the only option, because he did not want people to suffer strokes, but that diet offered a way without side effects⁴³. He also cited the Multiple Risk Factor Intervention Trial, saying men with signs of heart disease who were given diuretics died of heart disease 50% more often than those left untreated⁴⁴.

What all the experts say about high blood pressure

Diabetes

Pritikin linked diabetes to diet from the start: he said diabetes deaths fell during the war along with heart deaths²⁰. In 1982 he said his program could get nearly all type 2 diabetics off insulin and other medication within four to eight weeks⁴⁵. He cited his center’s study that August in Diabetes Care: 75% of type 2 patients on insulin were off it at four weeks, and 95% of those on pills were back to normal⁴⁶.

For type 1 diabetes he said a paper in press showed insulin doses cut by 40%, which he thought mattered because it could reduce complications such as blindness, kidney failure, stroke and heart attack⁴⁷. His VA hospital study had also taken adult-onset diabetics off insulin³⁸.

What all the experts say about diabetes

Cancer

Pritikin said the low-fat populations he studied rarely had breast, colon or prostate cancer²¹, and in 1982 he relied on a National Cancer Institute statement naming dietary fat as their main cause².

Asked about people who already had cancer, he said his diet carried no risk for them and might help, while admitting the evidence was only scattered isolated cases and “it’s not factual or proven yet”⁴⁸. He described a woman he took on in 1970 with linitis plastica, a stomach cancer given three to six months; he said she improved within weeks, ate solid food again after six to eight months and had no symptoms during the two years he followed her, and that although spontaneous remission happens, he doubted it in her case⁴⁹.

What all the experts say about cancer

Longevity and aging

Pritikin said the low-fat populations he studied did not die of the diseases he once thought came with aging but of old age, and that despite high infant mortality from poor sanitation, those past 40 outlived Americans, some reaching 100 or more while staying active⁵⁰. He put the gain in American life expectancy at 40 since 1900 at only about seven months⁵¹.

Asked in 1982 how long people on his diet should live, he answered seven times the age of puberty, 105 to 120 years, a rule he said holds for primates and other species⁵². He was 67 at the time⁵².

What all the experts say about longevity and aging

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