ape diet
n. A vegetarian diet that emphasizes soy protein, soluble fiber, nuts, and leafy green vegetables.
Examples
2003
What would Koko do? Koko, the gorilla who famously learned to communicate with sign language, was apparently not consulted on this latest study. But the Journal of the American Medical Association reported the other day that the best way to avoid a high cholesterol count may be to adopt what is affectionately called the "ape diet."

Those who conducted the brief but intense examination of diet concluded that eating the very things that our primate cousins prefer is just as effective as modern drugs in lowering levels of the bad cholesterol, known as LDL. The ape diet, heavy in whole grains, nuts, soy and fruits and vegetables, is also cheaper than medicine, has fewer side effects and, if properly prepared, tastes a heck of a lot better.
—“WWKD?,” Salt Lake Tribune, July 26, 2003
2003
Researchers found that a modernized "ape diet" — one that is high in fibre, nuts, soy and extracts of leafy greens — can reduce cholesterol by almost 30 per cent. …

Participants who took a 20-milligram daily dose of lovastatin and ate a vegetarian diet saw their LDL cholesterol fall 30.9 per cent.

Those who followed the same diet, but didn't take the drug, had reductions of only 8 per cent.

Members of the third group, who ate the customized [ape] diet, saw their LDL levels fall 28.6 per cent in four weeks.
—Andre Picard, “'Ape' diet a cholesterol-buster, researcher says,” The Globe and Mail, July 23, 2003
2001 (earliest)
Jenkins believes that the less we eat like our ancestors, the more likely we'll succumb to heart disease. …

Participants followed three evolutionary diets, each one for two weeks at a time. The oldest, the Great Ape Diet, consisted of fruits, vegetables, leafy greens and nuts, but no starch or animal foods. Volunteers munched their way through five kilograms of produce each day, taking in more than 100 grams of fibre, plenty of vegetable protein, little fat and virtually no cholesterol. …

To Jenkins' surprise, after one week on the Great Ape Diet, participants' LDL (bad) cholesterol levels dropped by 33 per cent, the same magnitude you'd see with cholesterol lowering drugs called statins. The Stone Age diet was about two-thirds as good, while the modern diet had only a modest effect on blood cholesterol.

Jenkins attributes these heart-healthy effects to three key ingredients — soluble fibre, vegetable protein, and naturally occurring compounds called plant sterols — all abundant in the ape diet.
—Leslie Beck, “Eat like the apes, researcher suggests,” The Toronto Star, May 07, 2001
Notes
This phrase was coined by Dr. David Jenkins, a professor of nutritional sciences at the University of Toronto. What does the diet consist of? Here's a typical day's menu, which was published recently in the Globe and Mail:

Breakfast — Hot oat-bran cereal; soy beverage; strawberries; sugar and psyllium; oat-bran bread; enriched margarine; double-fruit jam

Snack — almonds; soy beverage; fresh fruit

Lunch — Spicy black-bean soup; sandwich with soy deli slices; oat-bran bread; enriched margarine; lettuce; tomato; cucumber

Snack — Almonds, psyllium, fresh fruit

Dinner — Tofu bake with eggplant, onions and sweet peppers; pearled barley; vegetables

Snack — fresh fruit; psyllium; soy beverage