Category Archives: High-Protein Diets

Gary Taubes’ Typical Low-Carb Diet, And Lab Results

Proposed Warning Label For Meat: “Eating Meat Contributes To Insulin Resistance And Diabetes”

The California Senate just passed a bill requiring warning labels on sugar-sweetened beverages:

“Drinking beverages with added sugar(s) contributes to obesity, diabetes, and tooth decay.”

It’s a shame that sweetened beverages are being singled out. I would like to see a similar label on meat:

“Eating meat contributes to insulin resistance and diabetes.”

Why? Because meat-eating is a risk factor for developing diabetes:
Meat Consumption As A Risk Factor For Type 2 Diabetes, Nutrients, February 2014

Researchers evaluated studies that examined different amounts and types of meat consumption and the risk for developing diabetes. They found that meat-eaters had a significantly higher risk of developing diabetes compared with non-meat-eaters. Here’s a chart summarizing the results of one of the included studies, Type of Vegetarian Diet, Body Weight, and Prevalence of Type 2 Diabetes, Diabetes Care, 2009:

Mechanisms for meat’s effect on diabetes risk:

Effect on body weight – “Nearly all observational studies comparing meat-eaters with those who avoid meat show higher body weights among the former group, a finding mirrored in the results of intervention studies using meatless diets.”
Effect on visceral fat (fat around organs in abdominal area) – “Visceral adipose tissue is associated with insulin resistance as a result of increased proinflamatory cytokines.”
Effect on intracellular lipid (fat inside cells) – Impairs insulin action. This would involve, in part, the glucose transporter (GLUT4), which I discussed here.
Effect on iron balance – “Meat provides a substantial quantity of heme iron … a prooxidant that encourages the production of reactive oxygen species, which may damage body tissues, including insulin-producing pancreatic cells.” Even moderately elevated iron stores are associated with insulin resistance and type 2 diabetes.
Nitrates in processed meats – Nitrites and sodium are both linked to elevated diabetes risk.
Systemic inflammation – “A 2014 Harvard study reported that as total red meat consumption increased, so did biomarkers of inflammation.”
One they didn’t mention was presence of persistent organic pollutants (POPs): Animal Fat Is A Natural Reservoir For Environmental Pollutants. “There is now solid evidence demonstrating the contribution of POPs at environmental levels, to metabolic disorders … such as obesity and type 2 diabetes.”

Do you think a meat label could come to pass? There certainly is enough justification for it.

Animal Protein But Not Plant Protein Increases Risk For Diabetes

1 Reply

Diets high in animal protein – meat, eggs, seafood, cheese, yogurt and other dairy products – were associated with an elevated risk for type 2 diabetes. That was the finding of this new study:

Dietary Protein Intake and Incidence of Type 2 Diabetes in Europe: The EPIC-INTERACT Case-Cohort Study, Diabetes Care, 10 April 2014

It was large with a long follow up:

“The prospective European Prospective Investigation into Cancer and Nutrition (EPIC)-InterAct case-cohort study consists of 12,403 incident type 2 diabetes cases and a stratified subcohort of 16,154 individuals from eight European countries, with an average follow-up time of 12.0 years.”

It found:

“After adjustment for important diabetes risk factors and dietary factors, the incidence of type 2 diabetes was higher in those with high intake of total protein and animal protein. Plant protein intake was not associated with type 2 diabetes.

In view of the rapidly increasing prevalence of type 2 diabetes, limiting iso-energetic diets high in dietary proteins, particularly from animal sources, should be considered.”

It’s not news on this blog that animal foods raise the risk for diabetes. This study just adds to the growing body of evidence. Eat plants.

Low-Protein, High Carbohydrate Diet Linked To Longer Life

1 Reply

I’m bringing this post from March 5 up to the top because I wanted to add the figure to the right. It was part of the study, used to illustrate the effect of varying macronutrients.

While the low-carb, high-protein diets reduced food intake and body fat, they did so at the expense of lifespan and quality of life. Low-carb eating mice lived shorter lives and had worse health later in life.

The worst diet? High-fat, low-protein. The mice were fatter than the other groups, had poor health, and died early.
________

Eat Plants.

The Ratio of Macronutrients, Not Caloric Intake, Dictates Cardiometabolic Health, Aging, and Longevity in Ad Libitum-Fed Mice, Cell Metabolism, March 2014

The fundamental questions of what represents a macronutritionally balanced diet and how this maintains health and longevity remain unanswered. Here, the Geometric Framework, a state-space nutritional modeling method, was used to measure interactive effects of dietary energy, protein, fat, and carbohydrate on food intake, cardiometabolic phenotype, and longevity in mice fed one of 25 diets ad libitum. Food intake was regulated primarily by protein and carbohydrate content. Longevity and health were optimized when protein was replaced with carbohydrate to limit compensatory feeding for protein and suppress protein intake. These consequences are associated with hepatic mammalian target of rapamycin (mTOR) activation and mitochondrial function and, in turn, related to circulating branched-chain amino acids and glucose. Calorie restriction achieved by high-protein diets or dietary dilution had no beneficial effects on lifespan. The results suggest that longevity can be extended in ad libitum-fed animals by manipulating the ratio of macronutrients to inhibit mTOR activation.

And…

“Our results show that healthy aging is not achieved in mice fed high-protein diets and/or diluted diets to reduce calorie intake, but rather by low-protein diets (especially, we might predict, those low in BCAAs*), where additional energy requirements are met by dietary carbohydrates rather than fats.”

*BCAAs are Branched Chain Amino Acids (leucine, isoleucine and valine). Meat, dairy and other animal foods are good sources of BCAAs.

So, high-protein diets activate mTOR. mTOR is a protein “that regulates cell growth, cell proliferation, cell motility, cell survival.” A high level of mTOR signaling has been linked to cancer and Alzheimer’s Disease.

“Given the evidence that activation of mTOR is proaging, our results support this as a mechanism to explain the life-extending effects of a low-protein, high-carbohydrate diet.”

By the way, insulin also activates mTOR. People in the early stages of diabetes often have high levels of insulin – their pancreas is attempting to compensate for increasing insulin resistance brought about, in part, by eating too much fat, especially saturated fat. So…

Insulin resistance –> High insulin levels –> Activation of MTOR –> Cancer?

Having worked in the field of diabetes for years I know that “people with diabetes are at significantly higher risk for many forms of cancer.”

Diets High In Animal Protein, But Not Plant Protein, Linked To Cancer, Diabetes, And Earlier Death

3 Replies

Want protein? Eat beans.

I just posted about mice that lived longer and healthier lives when they ate low-protein, high carbohydrate diets. Because people will say “Great for the mice!” here’s a brand new study in humans that found the same thing:

Low Protein Intake Is Associated with a Major Reduction in IGF-1, Cancer, and Overall Mortality in the 65 and Younger but Not Older Population, Cell Metabolism, March 2014

Mice and humans with growth hormone receptor/IGF-1 deficiencies display major reductions in age-related diseases. Because protein restriction reduces GHR-IGF-1 activity, we examined links between protein intake and mortality. Respondents aged 50–65 reporting high protein intake had a 75% increase in overall mortality and a 4-fold increase in cancer death risk during the following 18 years.

These associations were either abolished or attenuated if the proteins were plant derived.

There was also a “5-fold increase in diabetes mortality across all ages.”

This was an epidemiological study that tracked 6,381 US men and women, 50 and over (NHANES III), for nearly 2 decades. It included a variety of ethnicities, education levels, and health conditions.

A few more excerpts from the study:

Notably, our results showed that the amount of proteins derived from animal sources [meat, fish, cheese, milk, eggs] accounted for a significant proportion of the association between overall protein intake and all-cause and cancer mortality. These results are in agreement with recent findings on the association between red meat consumption and death from all-cause and cancer.
Previous studies in the U.S. have found that a low carbohydrate diet is associated with an increase in overall mortality and showed that when such a diet is from animal-based products, the risk of overall as well as cancer mortality is increased even further.
The progression of both melanoma and breast cancer was strongly attenuated by the low protein diet, indicating that low protein diets may have applications in both cancer prevention and treatment.
In mice, the changes caused by reduced protein levels had an effect potent enough to prevent the establishment of 10%–30% of tumors, even when 20,000 tumor cells were already present at a subcutaneous site.

So, you can have cancer, but prevent it’s progression by eating a low-protein diet. Dr. Campbell, author of The China Study, must be breaking out the champagne.

Note, though, that when someone reached their mid-60s, a higher protein diet was found to be beneficial:

“Both high and moderate protein intake in the elderly were associated with reduced mortality compared to that in the low protein group, suggesting that protein intake representing at least 10% of the calories consumed may be necessary after age 65 to reduce age-dependent weight loss and prevent an excessive loss of IGF-1 and of other important factors.”

For these authors, less than 10% was considered low-protein, 10-19% moderate protein, over 20% high-protein. They found that even moderate amounts of protein had detrimental effects during middle age. However, they are advising people over 65 to get at least 10% of their calories from protein. Note, however, that risk for diabetes was still 5-fold at those older ages. So the protein they should be consuming should come from plant sources. Bean, legumes, peas, peanuts, soy products, nuts, and seeds are excellent sources of plant protein.

“These results suggest that low protein intake during middle age followed by moderate to high protein consumption in old adults may optimize healthspan and longevity.”

Here’s co-author of the study, Valter Longo (Professor of Biogerontology at USC Davis School of Gerontology, Director of USC Longevity Institute), from their press release:

“The majority of Americans are eating about twice as much proteins as they should, and it seems that the best change would be to lower the daily intake of all proteins but especially animal-derived proteins,” Longo said. “But don’t get extreme in cutting out protein; you can go from protected to malnourished very quickly.”

“Almost everyone is going to have a cancer cell or pre-cancer cell in them at some point. The question is: does it progress?” Longo asked. “Turns out one of the major factors in determining if it does is protein intake.”