Dr. Francis Pottenger was dedicated to preventing chronic disease. He had common sense and was an original thinker, which helped him to make a significant contribution to the understanding of how proper nutrition plays a major role in maintaining good health.
Pottenger conducted a feeding experiment, between the years 1932 and 1942, to determine the effects of heat-processed foods on cats. More than 900 cats were studied during this time. At the time he was making adrenal extract. The laboratory cats he was giving adrenalectomies, to standardize the hormone content of the extract, had a high mortality rate. There was no existing chemical procedure to standardize biological extracts, which made it necessary for manufacturers of these extracts to use animals to determine their potency. As a cat can’t live without its adrenal gland, the dose of extract needed to support its life can calibrate the extract’s potency.
He wanted to maximize the animal’s preoperative health so he fed them a diet of market grade raw milk, cooked meat scraps from the sanitarium and cod liver oil. The scraps included muscle, heart, brain, liver, tripe and sweetbreads. Their diet was considered to be rich in all the important nutrients as determined by the experts of the day. The adrenalectomies were as surgically exact in technique as could be performed at the time.
Pottenger was greatly puzzled as to why his cats were such poor operative risks. He sought an explanation and noticed they all showed signs of nutrition deficiency and a decrease in their reproductive capacity. Also many kittens were born with skeletal deformities and organ malfunctions.
His neighbors kept donating cats to his laboratory and because of the increase in animals the demand for cooked meat was greater than the supply. He was forced to place an order at the local meat packing plant for raw meat scraps, which included muscle, viscera and bone. These raw scraps were fed to a segregated group of cats and within a few months they appeared to be in better health than the ones eating the cooked meat. The kittens were more vigorous and their post-operative mortality decreased significantly.
The contrast in the health between the raw meat fed cats and the cooked meat cats was so startling to Dr. Pottenger it prompted him to conduct a controlled experiment. He had many questions he wanted answers to such as Why did the cats fed raw meat have a better survival rate then those fed the cooked meat? Why were the kittens, which were fed raw meat seem more vigorous? Why did the cooked meat diet seem to be lacking in nutrition? He felt a controlled study might answer these questions and provide insight into human nutrition.
There’s no experiment that is similar to Dr. Pottenger’s experiment in medical literature, making it totally unique. He consulted with Dr. Alvin G. Foord, professor of pathology at the University of Southern California and a pathologist at the Huntington Memorial Hospital in Pasadena, California. Their studies met the most rigorous standards of that time. They observed strict protocol. All variables were reported and explained. Despite this fact there is much misinformation being written and stated about the experiment. Some of what is being said is just not true.
He’s been criticized for a number of things. One being he had the cats in an artificial environment, but this is not valid, as they needed to be in a controlled environment. Another was applying the results to human nutrition. Pottenger didn’t say there was a one to one correlation, but he did state the similarities were quite obvious.
As previously stated, the study lasted for 10 years and the subjects were divided into two groups, the raw meat group and the cooked meat group.
The group of cats, which was fed raw meat, was fed 2/3 raw meat, 1/3 raw milk and cod live oil. They preserved a normal healthy body throughout each generation. Tissue tone and fur quality were healthy and there was little shedding of the fur. The calcium and phosphorus content of the cats’ femur bones were consistent. Their internal organs developed fully and functioned normally. Throughout their lifetime they were resistant to infections, fleas, and other parasites. They showed no sign of allergies. They were social, outgoing and friendly. When they were dropped from six feet to test their coordination, they always landed on their feet. Generation after generation was comparable in every way. The kittens, which were born, had an average weight of 119 grams. Miscarriages were a rare occurrence. Each litter averaged five kittens and the mothers nursed the newborn without difficulty.
The other group, the cooked meat group, was fed 2/3 cooked meat, 1/3 raw milk and cod liver oil. In the litter of kittens born in this group, each kitten was a different size and had a different skeletal pattern. Obvious deficiencies in the bones were revealed in x-rays; the long bones were increased in length and the diameters were decreased, and the internal structural mesh was coarser and showed evidence of less calcium. In the third generations the bones were as soft as rubber and osteogenesis imperfecta, a genetic bone disease, was present. This correlates to humans who mostly eat cooked food.
The cats on this diet developed heart disease, under-active thyroid or inflammation of the thyroid, nearsightedness or farsightedness, infections of the kidney, bladder, liver, testes or ovaries. They had inflammation of the joints, nervous system (with paralysis), meningitis, and obesity, except for the mother cats, which were under weight.
These cats would wheeze, sneeze and scratch and being irritable and nervous, they wouldn’t purr. All of these conditions were common among the cats and infections of the bones were often the cause of death. By the time the third generation was born, the cats didn’t survive beyond six months of age, which terminated the group.
Open microscopic examination of the lungs, it was determined the tissue was abnormal. The lungs showed edema (an excess of fluid), hyperemia (an excess of blood) and partial atelectasis (collapse of the expanded lung). The most deficient cats had bronchitis and pneumonitis.
Vermin and intestinal parasites were prevalent in this group. Many had skin lesions and allergies, which increased in frequency and severity from one generation to the next. The foremost cause of death in the adult cats was pneumonia and emphysema. Diarrhea and pneumonia was a principal cause of death among the kittens.
Miscarriages among pregnant females were common: 25% in the first generation and 70% in the second generation. The females’ deliveries were difficult and many died in labor. Autopsies showed ovarian atrophy and uterine congestion.The average weight of the delivered kittens was 19 grams less then the raw meat fed kittens.
Once the females were deficient in their diets for 12 to 18 months, they weren’t able to give birth to normal kittens. Even after three or four years of eating an optimum diet, the kittens still showed signs of skeletal and dental developmental deficiencies, although a gradual reversal and regeneration did occur if the kittens were maintained on this optimum diet.
Dr. Pottenger also experimented with milk. Cats, which were fed pasteurized milk as the main constituent in their diet, showed skeletal changes and lessened reproductive effectiveness. The kittens showed progressive constitutional and respiratory problems, similar to what was found in the cooked meat group of cats. Cats, which were fed evaporated milk, showed even more damage to their bodies. Cats, which were fed sweetened condensed milk, showed the most damage. They developed heavier fat deposits and severe skeletal deformities. They paced nervously in their cages and were extremely irritable. The life span of cats fed metabolized vitamin D milk was reduced to less than half. Metabolized vitamin D milk from cows fed irradiated yeast was even more harmful to the male cats.
Dr. Francis Pottenger found that only a diet containing raw milk and raw meat produced optimal health and longevity. The diet produced excellent bone structure and bone density, wide palates, which had plenty of room for teeth, shiny fur, no vermin or disease, ease in reproduction and gentleness in disposition.
He found that by cooking the meat or pasteurizing the milk (heat processed) it caused reproduction and physical degeneration, which increased with each generation. Vermin and parasites were abundant and skin ailments and allergies increased from 5% to 90%. Bones were soft and pliable. Personality changes occurred as well as hypothyroidism and every degenerative disease known to man. The cats died out by the fourth generation. What he found in his cats is similar to what is found in tribes that have abandoned their traditional diets.