An analysis published in July concluded that the meat-heavy ketogenic (or keto) diet could be harmful to those adopting it, even raising the risk of chronic disease.
What is a keto diet?
The keto diet involves consuming very low amounts of carbohydrates and high amounts of fat. Therefore, foods like eggs, meat (including fatty fish), full-fat dairy, and non-starchy vegetables are encouraged.
Meanwhile, those on a keto diet typically avoid beans and legumes, various fruits and vegetables, processed foods, pasta, bread, rice, oats, and cereals.
Consuming too few carbs forces the body to enter a metabolic state called ketosis. This results in the body burning more fat, rather than carbs, for energy.
Because of this, the diet became popular among those looking to lose weight quickly. However, a growing body of research suggests that the diet comes with a host of health risks.
The analysis – published in Frontiers in Nutrition in July – assessed the health risks and benefits of the keto diet.
Researchers noted that the diet has some benefits, such as lowering the frequency of seizures for those with drug-resistant epilepsy.
However, for most people, the ‘risks of such diets outweigh the benefits’, the analysis reads.
“Such diets affect diet quality, typically increasing intake of foods linked to chronic disease risk and decreasing intake of foods found to be protective in epidemiological studies,” researchers wrote.
“Low-carbohydrate diets are often low in thiamin, folate, vitamin A, vitamin E, vitamin B6, calcium, magnesium, iron, and potassium,” they also said, adding that those following low-carb diets could have nutritional deficiencies.
Very-low-carb diets could increase the likelihood of chronic disease, the review says.
It reads: “Foods and dietary components that typically increase on ketogenic diets (eg, red meat, processed meat, saturated fat) are linked to an increased risk of [chronic kidney disease], cardiovascular disease, cancer, diabetes, and Alzheimer’s disease, whereas intake of protective foods (eg, vegetables, fruits, legumes, whole grains) typically decreases.”
Additionally, pregnant people on keto diets are more likely to give birth to a child with a neural tube defect, researchers noted.
A study published in 2018 found that low-carb diets could shorten life expectancy. Researchers assessed the diets of more than 15,000 people for an average of 25 years.
They found that those who obtained around half of their energy from carbs had a lower risk of death than those consuming too few or too many carbs.
The research stated that diets that relied more so on animal-based protein like beef, chicken, pork, and lamb were linked with higher mortality rates.
The opposite was true for diets that prioritized plant-based proteins and fats.
“These data also provide further evidence that animal-based low carbohydrate diets should be discouraged,” the study reads.
“Alternatively, when restricting carbohydrate intake, replacement of carbohydrates with predominantly plant-based fats and proteins could be considered as a long-term approach to promote healthy ageing.”