A Low-Carbohydrate or Keto Diet May Shorten Life

Like any other elimination diet , a low-carbohydrate or ketogenic diet may help you lose weight quickly and see positive results, but what are the long-term health effects? In 2018, Lancet published comprehensive research examining the eating habits of 432 thousand people worldwide. Researchers found that severely reducing carbohydrates (sugar) or trying to eliminate them while increasing animal-based protein and fat intake may lead to premature death.

A sentence from the study: “Replacing carbohydrates with animal-derived fat or protein increases mortality, but plant-based substitutions (vegetables, nuts, peanut butter, and whole-grain bread) decrease mortality… The source of carbohydrates changes the relationship between carbohydrate intake and death.”

Study author and cardiologist Dr. Sara Seidelmann said:

“We need to look very carefully at the protective components of healthy dietary compounds. Replacing carbohydrates with protein or fat, low-carbohydrate diets are becoming widely popular for health and weight loss. However, our data suggest that these popular animal-based low-carbohydrate diets may be associated with shorter overall life expectancy and shouldnot be encouraged.”

The figure above shows the relationship between dietary carbohydrate proportion and atherosclerotic heart disease risk (blockage of vessels supplying the heart). Risk is higher when carbohydrate intake is very low or very high (dark blue line).

Presented at the European Society of Cardiology, another recent study supported this research, appearing under the headline “Low-Carbohydrate Diets Are Unsafe and Should Be Avoided.” Study author Professor Maciej Banach said, “A low-carbohydrate diet was associated with earlier death. Diets low in carbohydrates and high in animal fat and protein, with respect to coronary heart disease, stroke, and cancer among various chronic diseases, increase the risks; these diets should be avoided.” he said.

This study examined 24.825 people for associations between low-carbohydrate diets, all-cause mortality, coronary heart disease deaths, and cancer. People consuming the fewest carbohydrates had, compared with the highest-carbohydrate group over six years, a % 32 higher risk of death . Risks of death from heart disease and cancer were also increased by 51 percent and 35 percent, respectively.

Professor Banach said: “Low-carbohydrate diets may help in the short term with weight loss, lowering blood pressure, and improving blood sugar control, but our study suggests they are linked over the long term to increased cardiovascular, stroke, and cancer mortality.”

The research does not provide a definitive causal answer, but Professor Banach says: “Reduced fiber and fruit intake and increased animal protein, cholesterol, and saturated fat with these diets may play a role."

Strict low-carbohydrate diets generally restrict carbohydrates to less than 50 grams daily. Ketogenic, Paleo, Atkins , and other low-carbohydrate diets sometimes fall into this category, depending on strictness.

- Related topic: List of the Healthiest and Most Effective Diets – 2019

You can lose weight on low-carbohydrate diets such as keto, but this appears to be an unhealthy solution. Keto dietitians greatly reduce clients’ sugar intake, but this also eliminates healthy carbohydrates.

Research shows that the longest-lived, healthiest people eat more plant-based foods, including fiber-rich carbohydrate foods. The best-known example is people in Blue Zones .

Research in Blue Zones shows that the world’s longest-lived people eat diets rich in whole grains, legumes, nuts, and leafy greens. Their diets are 90-95 percent plant-based, with most daily energy intake—50-65 percent—coming from healthy carbohydrates.

Healthy carbohydrates are not heavily processed foods like white bread or sugary drinks, but sweet potatoes, beans, whole grains, fruits, and vegetables as whole foods.

In conclusion , current global research suggests that focusing on healthy, plant-based whole foods is a better long-term dietary strategy than low-calorie diets. The best example is the Mediterranean diet.

Note: The ketogenic diet is being tested in medical conditions such as epilepsy . For its use in disease, you may wish to read our article New Evidence on the Medical Use of the Ketogenic Diet – Which Patients Benefit? .

In the list below, to help people achieve healthier, longer lives, information about the healthiest and unhealthiest diets is summarized.

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