Do High Protein Diets Really Cause Early Death?

A new report on Cell Metabolism shows that middle-aged individuals between the ages of 50-65 who eat a high-protein diet are four times more likely to die from cancer than those who ate a low protein diet. Those middle-aged people who consumed high-protein diets also had a 74 percent increase in mortality.

This study shows that a diet high in protein is bad for the middle-aged, but actually good for the elderly. Valter Longo, the scientist who led the study, said a high-protein diet is almost as bad as smoking.

While other studies have shown that diets high in protein can actually help aid in weight loss and a healthier lifestyle, this new study seems to be contradicting. According to the new study, high-protein diets may help you lose weight and build muscle, but too much will cause an early death.

According to Longo, these diets were made with a short term vision and people never really knew what affect these kind of high-protein diets would have after a while. “On a high-protein, high-fat diet you can lose weight, but in the long run you may be hurting yourself.”

The main point stated in the report is that high-protein diets lead to increased levels of IGF-1.

IGF-1 is short for insulin-like growth factor. This is a hormone in the body that plays an important role in childhood growth and development. It also has a very similar molecular structure to insulin and is commonly used by bodybuilders for it’s anabolic effects.

IGF-1 is linked to an increased risk of cancer and the more protein you eat, the more IGF-1 your body is able to produce.

The report has two separate studies. One conducted using mice, the other humans.

The one conducted using mice, was done by giving 858 mice 25 different diets. Each one ranging in protein to carbohydrate ratios. The mice fed the most protein were leaner but didn’t live as long.

The study using humans took place over an 18 year time period, and surveyed 6,381 adults on their diets over a 24 hour period of time.

The subjects were divided into three different groups based on what they ate. High, moderate, and low-protein. The ones in the high protein group were the same group mentioned at the beginning of this article. They were four times more likely to get cancer and had a 74 percent increased mortality rate.

Now this study only shows what people ate in 24 hours. This doesn’t mean they ate the same amounts of protein everyday. So don’t take this study as absolute fact because the evidence it’s based off of isn’t conclusive enough to really be worried about. If you’re an athlete or bodybuilder that eats a high-protein diet, don’t change your diet because of this one study, but be aware that there are potential risks to eating large amounts of protein.

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