Middle-aged? Then meat and cheese could kill you

FIRST the bad news. High meat and cheese consumption during middle age makes you nearly twice as likely to die and four times more likely to die of cancer. That’s a mortality risk factor comparable to smoking.

According to a new study that tracked a large sample of adults for nearly two decades, diet rich in animal proteins during middle age makes you four times more likely to die of cancer than someone with a low-protein diet — a mortality risk factor comparable to smoking.

The study* published in Cell Metabolism (March 4) said protein-lovers were 74% more likely to die of any cause within the study period than their more low-protein counterparts. They were also several times more likely to die of diabetes.

Rates of cancer and death also did not seem to be affected by controlling for carbohydrate or fat consumption, suggesting that animal protein is the main culprit.

That’s really bad news for followers of protein-heavy diets such as Paleo and Atkins, which have been controversial but remain popular.

And the good? Seniors above 65 benefit from moderate protein intake, the study also said. Crucially, the researchers also found that plant-based proteins, such as those from beans, did not seem to have the same mortality effects as animal proteins.

The researchers define a “high-protein” diet as deriving at least 20% of calories from protein, including both plant-based and animal-based protein. A “moderate” protein diet includes 10-19 percent of calories from protein, and a “low-protein” diet includes less than 10% protein.

Definitive correlation

Before this study, researchers had never shown a definitive correlation between high protein consumption and mortality risk.

What differentiates this study is that the researchers considered biological changes as a result of age and how what’s good for you at one age may be damaging at another.

“There’s a misconception that because we all eat, understanding nutrition is simple. But the question is not whether a certain diet allows you to do well for three days, but can it help you survive to be 100?” said corresponding author Valter Longo, the Edna M. Jones Professor of Biogerontology at the USC Davis School of Gerontology and director of the USC Longevity Institute.

Rates of cancer and death also did not seem to be affected by controlling for carbohydrate or fat consumption, suggesting that animal protein is the main culprit

The latest paper draws from Professor Longo’s past research on IGF-I, including on an Ecuadorian cohort that seemed to have little cancer or diabetes susceptibility because of a genetic mutation that lowered levels of the growth hormone IGF-I. Protein controls the growth hormone IGF-I, which helps our bodies grow but has been linked to cancer susceptibility.

The study shows that older adults over 65 who ate a moderate- or high-protein diet were less susceptible to diseasNike