Just about everyone has heard of the latest advertised “keto diet,” but should it be considered a healthy diet? Many dietitians and other nutrition experts have concerns about its safety. They cringe that yet another fad diet for weight loss is on the market.

It is considered a fad diet, because as a diet it is not balanced in the recommended distribution of proteins, fats and carbohydrates. The other problem with this diet is that it does not allow eating in moderation; you cannot do it one day and then stop the next. The reason for this is that the diet is designed to place your body in a metabolic state called ketosis where it doesn’t feel hunger. However, there are adverse effects of being in a state of ketosis such as: nausea, fatigue, constipation, low blood pressure, elevated uric acid (a normal body waste produce usually released in urine), kidney issues, gout, and a stale, foul taste in the mouth.

Because of these side effects the diet tends not to be sustainable.

If you have read about the keto diet, you know that it is basically a high-fat, moderate-protein diet with an extremely low intake of carbohydrate-containing foods.

A typical intake of carbohydrates in an average diet should be at least 100 grams per day, whereas the keto diet only recommends between 20-30 grams per day. Carbohydrates provide the body with glucose, a sugar found in fruits and vegetables, which most people consider to be healthy foods packed with vitamins. Carbohydrates are also found in grain-based foods such as pasta, bread, crackers, etc., which some people consider not as healthy, especially if they are trying to lose weight.

Another food group that is limited in the keto diet is the dairy group, except for high-fat cheeses and heavy cream. No milk or yogurt is included, because even though they have varying amounts of fat, they also are a source of carbohydrates. But without eating carbohydrate foods, the dieter is not getting enough glucose or the needed vitamins, minerals and fiber that are vital to their health.

The glucose from eating carbohydrate foods (fruits, vegetables, milk and grains) gives the body energy. Without carbohydrate sources, our bodies must break down fat for energy. Because fats do not break down completely, they are not the body’s preferred source of energy. In fact, if we use fat for energy, our body goes into a metabolic state called ketosis, hence the name “keto” diet. Many of the adverse effects from the ketosis result in the outcomes in the body mentioned in the list above.

Some individuals think that ketosis is the key to losing weight, but when studies compared the keto diet to a typical weight loss diet, they found that both will produce a reduction in weight. However, once people stop eating the keto diet, they begin a terrible cycle of weight loss and weight regain, often gaining an even higher level of the initial pounds lost.

A diet for weight loss containing the suggested food groups is more sustainable to keep the weight off for the long-term.

Cindy Javor is a Penn State Extension nutrition educator and Nutrition Links supervisor in Allegheny County.