A major new study in the journal Cell Metabolism is getting a lot of attention right now because it links high consumption of protein to a 75% higher death rate. It says that people 50 to 65 years old who eat a high level of protein (20% or more of calories) compared to those who eat a low level (9% or less) are:
- 4 times more likely to die of cancer
- 5 times more likely to die of diabetes
- 73 times more likely to get diabetes if you have no current symptoms
People in the mid-range of protein eaters (10 to 19% of calories) would be 3 times more likely to die of cancer than someone who eats 9% protein or less. They are be 23 times more likely to get diabetes, too.
Proteins from animals "promote mortality"
The increased risks of disease and death from eating high levels of protein are even more startling when you realize that the risks are higher for those who eat a lot of protein from animals. The study says:
However, when the percent calories from animal protein was controlled for, the association between total protein and all-cause or cancer mortality was eliminated or significantly reduced, respectively, suggesting animal proteins are responsible for a significant portion of these relationships. When we controlled for the effect of plant-based protein, there was no change in the association between protein intake and mortality, indicating that high levels of animal proteins promote mortality and not that plant-based proteins have a protective effect.
The researchers recommend that the Food and Nutrition Board of the Institute of Medicine change its current recommended protein intake to its current minimum. That puts it right in line with The China Study and the menus and recipes here at Cook for Good. The board's current recommendation is 1.0–1.3 grams of proteins per kilogram of body weight per day, with a minimum intake of 0.7 to 0.8 grams per day. For someone who weights 100 pounds, that would be a drop from a range of 45 to 59 grams of protein a day to a ranger of 32 to 36 grams. That is the amount of protein in a cup of shelled walnuts, a half cup of raw spinach, or a half ounce of cooked salmon.
Plants can provide plenty of protein, often more than meat per calorie
If you've become used to the restaurant slang that uses "protein" to mean "beef, pork, chicken, or fish," take a look at the two charts below. The first shows top plant sources of protein. (Cook for Good supporting members can log in to see my complete chart showing the protein in 38 vegetables, fruits, grains, and nuts in the Bonus Material section). The second chart shows common animal sources of protein. Notice that basil has more protein per calorie than pork chops, raw spinach has more than salmon, and red cabbage has the same amount as pepperoni--all at a fraction of the cost.
Read on for a chart of protein from animal sources and more on the study, plus how you can eat for health...