and 10 people on 100% fruit (also 10 different varieties) for 10 months and have them doing athletic output etc and see how they go emotionally, physically and nutritionally.
There are a few case studies in the medical literature of people who have lived on fruit exclusive diets.
In this one,
Brain & Development 29 (2007) 369–372,
...the subject consumed nothing but about 20 bananas a day for 2 years (and drank 500 mls of water).
"During the period of massive banana eating habit, she showed increase of serum potassium (from 4.7 mEq/l to 6.1 mEq/l) and whole blood dopamine (from 11 ng/ml to 210 ng/ml; normal range 0.5–6.2 ng/ml), and obvious dysthymia that is inexplicable only by the pathology of AN. When the patient resumed other food ingestion after 26 months of obsessive and restricted eating of banana, the abnormalities in her blood data and her psychological state were all corrected toward normal. We conclude that in this case, the obsessive and restricted habit of banana ingestion resulted in hyperkalemia, hyperdopaminemia, and psychological change."
In this case,
Int J Eat Disord 2008; 41:376–379,
(with "quotes" ) ...the subject was admitted and was "cachectic, disheveled, and malodorous, with a non healing, unattended facial lesion." Turns out that "decades earlier" he had written a "health book on nutrition and was overzealous & rigid with which he followed his unusual diet apparently contributed to his divorce years ago." "he ordinarily drank no water, as he believed his diet would provide a sufficient supply. Initially, he had felt that only grains, vegetables, and fruits were needed to survive, but over the years he further restricted his diet almost entirely to fruit." He had followed a ‘‘fruitarian’’ diet for many years and had apparently told his daughter that he did not need treatment for his facial lesion as his diet would ‘‘take care of it.’’
"His complete blood count was significant for a low red blood count (4.43 3 106 per ml) and serum hemoglobin (14.1 g/dl) and a high mean corpuscular volume (100 fl). Folate was slightly elevated (20.1 ng/ml). "Low values were found for serum iron (39 lg/dL), ferritin (13 ng/ml),\ and iron saturation (14%)."
"He was diagnosed with cognitive disorder NOS, Asperger’s syndrome and Schizotypal traits, EDNOS (nor specified eating disorder) and Dementia secondary to nutritional deficiency (B12). Cognitive testing showed marked retrieval deficits and signs of executive dysfunction consistent with subcortical dementia. "
From the article, One hundred years ago A converted "Fruitarian" BMJ 2000;321:1331 ( 25 November ) (From an article that appeared 100 years earlier in the BMJ)
"Mr. Hector Waylen, who not long ago was a militant “fruitarian,” and taught that fruits and nuts were the “natural and ultimate food” of mankind, has had his eyes opened to the error of his dietetic ways, and frankly confesses the fact in the Bradford Truth Seeker. Since 1894, when he preached vegetarianism in Bradford, he has travelled round the world, has lost his health and slowly recovered it, has studied many things of which he was ignorant—among them, as we gather, the philosophy of food. For about eight years he was a vegetarian of the strictest kind.."
Also, Dr Benesh, a well respected Natural Hygiene doctor, told of the problem he encountered in people he had cared for who attempted a fruitarian diet--even on high-quality fruits available in season--for more than a few to several months. Benesh listed the following symptoms of people on long-term fruitarian diets that he had seen in his own Natural Hygiene practice,
-[R]idged nails, gingivitis, dental caries, dry skin and brittle hair, lowered red blood cell count and low hemoglobin percentage. Over a long period of time (at least one year or more) the blood serum level drops to a point of an impending pathological state if not corrected.
- Many of them display serious signs of neurological disorders, while some experience emotional upsets and extreme nervousness and often complain of insomnia. When their nutritional program is corrected these signs disappear and the patient finds himself in a much improved state of health.
Benesh, Gerald (1971) "Excessive fruit eating." Ahimsa, vol. 17, no. 3 (May/Jun. 1976), pp. 1-2. (Reprinted from Dr. Shelton's Hygienic Review, Apr. 1971)
Jay Dinshah, a long-time vegan and founder of the American Vegan Society, published an extensive article series on fruitarianism in the late 1970s, titled "Fruit for Thought," in his own newsletter Ahimsa. Of the people who had lived on truly fruitarian diets, failure was the rule, not success.
Dinshah, H. Jay, (1976-77) "Fruit for thought: should man live by fruit alone?" (a 4-part article series). Ahimsa; Part 1 in vol. 17, no. 2 (Mar./Apr. 1976), pp. 1, 4, 7-8; Part 2 in vol. 17, no. 3 (May/Jun. 1976), pp. 1, 7-8; Part 3 in vol. 17, no. 4 (Jul./Aug., Sept./Oct., Nov./Dec. 1976 combined issue), pp. 1-9, 11-12; Part 4 in vol. 18, no. 1 (Jan./Mar. 1977), pp. 1-3, 5-8.
it would be a fun experiment to put 10 people on 100% grains (say 10 different varieties) with no condiments etc
There are a few case studies in the medical literature of people who have lived on starch (or near starch) exclusive diets and some great studies on people who live on a near starch exclusive diets.
In this study,
The value of whole potato in human nutrition, Biochem J. 1928; 22(1): 258–260.
..the subjects at virtually a diet of 100% potatoes.
"An experiment is described in which two adults, a man and a woman, lived over a period of 167 days in nitrogen equilibrium and in good health on a diet in which the nitrogen was practically solely derived from the potato."
"The digestion was excellent throughout the experiment and both subjects felt very well. They did not tire of the uniform potato diet and there was no craving for change. We think that our results must be looked upon as a confirmation of the experiment of Hindhede, and the high value of potato as a source of nitrogen for the human adult seems to be confirmed."
As mentioned in the study, they were confirming similar experiments that had been done earlier..
Hindhede (1913, 1). Skand. Arch. Physiol. 30, 97. (1913, 2). Protein and nutrition (Ewart, Seymour, and Co., London).
Also, as described in...
The Effect if Food Restriction During War on Mortality in Copenhagen. Journal of the American Medical Association v.74, n.6, 7feb20 M. Hindhede
"As research had also shown that man can retain full vigor for a year or longer on a diet of potatoes and fat and for Half a year or more on a diet of barley and fat,5 reliance was placed on our potatoes and the large barley crop, which was given to man and not to the pigs, as heretofore, with the result that the pigs died of starvation, but the people received sufficient nutrition. "
5. Hindhede, M.: Skand. Arch. f. Physiol. 35: 291.
The following are not 100%, but close...
... the long lived Okinawans got 69% of their calories from sweet potatoes, another 19% from rice, wheat and barley (which totals 88%) and another and 6% from legumes (which makes 94% from cooked starches). They are not only one of the longest lived populations, but also one of the longest lived without disability and in good health. Their disease rates are for many of the chronic diseases are some of the lowest. Fruit was less than 1% of their calories.
Caloric Restriction, the Traditional Okinawan Diet, and Healthy Aging
The Diet of the World’s Longest-Lived People and Its Potential Impact on Morbidity and Life Span Ann. N.Y. Acad. Sci. 1114: 434–455 (2007).
Earlier in the decade, around the turn of the century, many of them, actually got up to 93% of their calories from sweet potatoes alone. These would be the same ones who became Centenarians today.
History and characteristics of Okinawan longevity food Asia Pacific J Clin Nutr (2001) 10(2): 159–164
The longed lived and healthy Chinese Centenarians, got 55% of their calories from sweet potatoes, grains made up another 15% (totaling 70%), beans another 9%, meaning 79% of their calories came from starchy vegetables. Vegetables made up another 9% and fruit was a small part.
A survey of the dietary nutritional composition of centenarians. Chinese Medical Journal 2001, 114 (10):1095-1097
In regard to performance, the Tarahumara Indians are world renowned for their ability to run long distances (sometimes over 100 miles at a time), and virtually no sign of any of the chronic diseases we die from. Around 71% of their calories come from corn and 19% from beans which means 90% of their calories come from starchy vegetables. Fruit is a very small part.
The food and nutrient intakes of the Tarahumara Indians of Mexico. The American Journal of Clinical Nutrition 32: APRIL 1979, pp. 905-915.
While not perfect and I am sure there are points on all that many may argue with, these are clearly some very interesting studies that have left us some very good evidence and clues.