Yes, Keto Can Be Bad for Your Heart

If you've looked into trying the keto diet, you've no doubt already encountered some of the associated controversies.

For starters, its intended purpose didn't begin as weight loss. The ketogenic diet was developed in the 1920s as a treatment for epilepsy, as it alters neurotransmitter levels in the brain and reduces seizure risk.

And intentions aside, it's a pretty intense lifestyle choice. When you eat keto, you obtain 60 percent to 90 percent of your calories from fats, while restricting carbohydrate calories to below 5 percent to 10 percent of total calories consumed. The biochemical result of this extremely low-carb diet is a state called ketosis, in which the body breaks down fats instead of glucose (from carbs) for energy.

With Oprah's 1988 public endorsement of the ketogenic Optifast liquid diet drink, keto began shifting from medical treatment to a popular fad diet.

The ups of keto...

The results are largely anecdotal, but a low-carb, high-fat (LCHF) diet such as keto may curb appetite and increase weight loss, particularly in the abdomen.

In a 2013 study published in Nutrients, 89 obese adults followed a six-month keto Mediterranean diet followed by a six-month Mediterannean maintenance diet and exhibited a significant mean 10 percent weight loss with no regain after one year.

Besides appearances, keto has also been reported to reduce triglycerides and increase HDL ("good") cholesterol. It has also been shown to reduce blood sugar and insulin, and improve blood pressure and metabolic syndrome. It may also be helpful to individuals with Alzheimer's, Parkinson's, polycystic ovary syndrome (PCOS), type 2 diabetes and other conditions.

...and the downs

Less pleasant side effects of eating keto include "keto flu," which sets in when you first cut down on carbohydrates before the body becomes accustomed to being fueled predominantly by fats. These symptoms, which subside in about a week, include fatigue, headache, brain fog and upset stomach. Long-term negative side effects include possible vitamin and mineral deficiencies, diarrhea, decreased athletic performance and reduced muscle mass and metabolism.

It's true most eating programs have some degree of side effects, but these are generally manageable for many people and not everyone will experience all of them. Unfortunately, what's listed above is just the tip of the iceberg.

The vast majority of keto diets derive their key component, fats, from animal products. These diets wind up being extremely high in meat, butter, cheese, eggs and other high-fat items, while low in most fruits and whole grains. Fats from hydrogenated oils and processed foods are commonly incorporated, both of which are dangerous for heart health, and herein lies the problem with keto.

Animal products contain fewer healthy fats and higher levels of cholesterol. Cholesterol builds up inside the walls of arteries as plaque, impeding blood flow and contributing to atherosclerosis, the hardening and narrowing of arteries. This, in turn, can lead to high blood pressure and increased risk for metabolic disease, heart disease and stroke.

Fats from hydrogenated oils and processed foods are commonly incorporated, both of which are dangerous for heart health, and herein lies the problem with keto.

Eating keto has also been linked to kidney stone production, osteoporosis, liver disease and a plethora of other medical issues.

Suddenly, a diet intended to improve health is increasing the risk for serious chronic illnesses, some of which can be fatal. While these side effects may be short-lived if keto is applied for weight loss for a short period of time, with the individual resuming a more balanced diet for weight maintenance, going keto long-term with high animal product consumption can be dangerous.

Notably, studies that have indicated benefits from a keto diet have largely looked at those lower in animal products. This masks the reality of what most keto participants will experience. A 2020 study from The American Journal of Medicine highlights these issues and cites the increased risk of heart and cardiovascular diseases associated with the keto diet (and intermittent fasting).

Revising your approach

If high cholesterol from animal products makes keto untenable, there's an alternate path: pivoting to plant-based keto. Rather than sourcing most fats from meats, dairy and eggs, try getting them from nuts, seeds, avocados and olive oil, and opting for plant-based protein sources, such as tofu, edamame and seitan.

Here's why: Plant-based diets consistently have been associated with decreased risk for cardiovascular disease, reduced morbidity and mortality, and increased life span. It is well-documented that people who eat plant-based foods have lower average total cholesterol and blood pressure, and significantly decreased risk for heart disease and stroke. If you don't want to go vegetarian or vegan, incorporate fatty fish, another good source of healthy fats. Minimize or avoid fats from processed foods, hydrogenated oils, meats and dairy, and avoid trans fats entirely.

While keto on a plant-based diet may initially sound frightfully restrictive, there are more options available to you than you realize. However, it's certainly not the only path to better health. Talk to your doctor or dietitian about your health concerns to determine the best food choices for your lifestyle.