This article was first published in聽
鈥淏ecome a vegetarian!鈥� was Swami Satchidananda鈥檚 advice to young Dean Ornish, who asked about improving his health. In 1972, Ornish was stricken with mononucleosis followed by a bout with depression that forced him to drop out of Rice University. While at home, he met the swami who had been teaching meditation techniques to his sister. That sparked Ornish鈥檚 interest and prompted a discussion that resulted in the advice not only to embrace vegetarianism, but to explore yoga and meditation as well. Ornish did, and soon felt well enough to continue his education, this time at the Baylor College of Medicine.
Seeing patients who were suffering from heart disease, often accompanied by depression, Ornish began to wonder if the program that had solved his problems would work for others. He enlisted a small group of patients who were willing to try his regimen and taught them about diet, exercise and yoga. Within weeks, they felt better, experienced less chest pain and had lower cholesterol. This turned out to be a pivotal moment in Ornish鈥檚 life and one that would define his career. He would dedicate himself to studying whether heart disease can be prevented and even reversed by diet and other lifestyle factors.
Of course, the idea that food and health are intimately connected was not novel. As early as the second century AD, the Greek physician Galen described the relation between food and health in his work On the Power of Foods. Neither was the connection between diet and heart disease new. In 1908, Russian physician Alexander Ignatowski published a paper in which he described the arteries of rabbits fed a diet of full-fat milk, eggs and meat being blocked by a buildup of fats and cholesterol. Then in 1913, Nikolai Anichkov, another Russian, showed that feeding cholesterol to rabbits causes atherosclerosis, the hardening of arteries due to a buildup of fatty deposits known as 鈥減laque.鈥� The question of whether dietary fats and cholesterol can also affect human arteries was not raised until the 1940s.
Lester Morrison graduated from 成人VR视频, earned a medical degree from Temple University in Philadelphia and went on to practise medicine in Los Angeles. Reading about Anichkov鈥檚 experiments sparked an interest in heart disease that was furthered by noting records that showed a drop in the disease during wartime when food supplies became critical, but increased in peacetime when food was plentiful. Since he had plenty of heart disease patients in his practice, Morrison decided to carry out an experiment. In 1946, he assigned 86 men and 14 women who had suffered a heart attack to a low-cholesterol, low-fat diet and a similar number of patients who would serve as controls were asked to follow their normal diet.
Although this was not a double-blind, properly randomized trial, it was the first experimental test of the relationship between diet and heart disease in humans. After three years, body weight and blood cholesterol had dropped in the test group, anginal symptoms decreased while exercise tolerance increased. More significantly, 30 per cent of the subjects in the control group died and only 14 per cent in the test group. Morrison followed both groups for another five years, after which the mortality rate was 44 per cent in the test group and 76 per cent in the control group. Judging that the study was too small and of questionable methodology, the medical establishment did not pay much attention.
In the meantime, researchers followed up on Anichkov鈥檚 rabbit feeding studies. John Gofman at the University of California centrifuged the blood serum of cholesterol-fed rabbits and identified two types of cholesterol, both of which were attached to proteins that enabled them to be transported through the blood. One type floated to the top of the serum sample and was termed low-density lipoprotein cholesterol (LDL) while the other deposited at the bottom, earning the name high-density lipoprotein cholesterol (HDL). The two types of cholesterol were also found in human blood samples and Gofman showed that men who had suffered a heart attack had elevated LDL and low HDL. Then in 1952 Laurence Kinsell published a study in the American Journal of Clinical Nutrition documenting a decrease in LDL with ingestion of plant foods and the avoidance of animal fats.
At this point, the story took an interesting twist, thanks to Nathan Pritikin, who was neither a physician nor a nutritionist. Pritikin had made a fortune as an entrepreneur and was totally shocked when in 1955, at age 40, a routine electrocardiogram revealed heart disease. The opinion at the time was that there was nothing to do except avoid both physical and mental stress. Pritikin decided to 鈥渄o his own research,鈥� something we are often advised to do by today鈥檚 self-appointed nutritional gurus. He came upon Morrison鈥檚 small study and since he lived nearby, made an appointment. A blood test found his cholesterol to be high and Morrison suggested he try the low-fat diet. Pritikin went all in, adopted a strict vegetarian regimen and, ignoring the recommendation about avoiding exertion, began a program of exercise. His blood cholesterol dropped dramatically and he became convinced he was beating his heart disease. A subsequent cardiac stress test during which he ran nearly 13 kilometres on a treadmill indeed showed normal heart function.
Thoroughly taken by his results, Pritikin became an evangelist for his diet and exercise regimen and began to fund medical studies. He educated himself thoroughly and gave talks about his experience, eventually garnering national attention, especially after the publication of his book, The Pritikin Program for Diet and Exercise, in 1979. Pritikin was even invited to speak at medical conferences and, although some criticized his diet as being too extreme, he earned a solid reputation in the medical community. Pritikin ended up punctuating the benefits of his program posthumously. In 1985, in the final clutches of leukemia, he died by suicide. As required by law, an autopsy was performed: There was a near absence of atherosclerosis. Furthermore, his heart鈥檚 pumping function had been completely uncompromised before death. But a proper, randomized trial to document the reversal of heart disease by diet and exercise was still missing.
It was such a trial that Ornish eventually carried out. Just a year after Pritikin鈥檚 death, 48 patients with coronary disease were randomized into an experimental group that would follow a strict vegetarian diet, a program of exercise as well as stress management training that involved yoga and meditation. After five years, the 28 patients who followed the program had fewer cardiac events and showed regression in the blockage of coronary arteries. Although the study was small, it demonstrated that lifestyle factors can at least in some cases play an important role in reversing heart disease.
Ornish always recognized Swami Satchidananda as having inspired his research and even wrote the forward to the swami鈥檚 Healthy Vegetarian cookbook. Vegetarianism and yoga worked for the swami who was healthy up to his death at age 88. Unfortunately, it seems he may have been into more than vegetarianism. His reputation is marred by allegations that he used his spiritual authority to coerce women into sexual relationships.
