The keto diet is THE big diet right now. Celebrities, like Halle Berry and Megan Fox, made it popular a few years back and it took off as the best way to lose all those unwanted pounds. Regardless of its popularity, is the keto diet healthy? Let’s discuss the keto diet overview.

What is the Ketogenic Diet?

The ketogenic or “keto” diet is a high fat, very low carbohydrate diet. It was originally used as a treatment for epilepsy before medications for this condition were available. It found a renewed popularity in the late- 1990s due to a TV movie about a boy whose untreatable epilepsy improved with keto.

The definition of a keto diet is to limit carbohydrates to 20-50 grams per day in order to reach a metabolic state called ketosis. When you are in ketosis, the body switches from burning sugar as its primary fuel source to burning fat. It takes more calories to use fat for energy, so this slightly speeds up metabolism. Being in ketosis also alters hormone levels, which in turn promote an increased feeling of fullness.

Benefits of the Keto Diet

There are several possible benefits to the keto diet. The first is rapid weight loss. Keto helps with weight loss by slightly speeding up metabolism. It also lowers insulin, which acts as a “storage” hormone in the body. When insulin is low, the body starts burning up stored fat. It is also a higher protein and fat diet, both of which are highly satiating macronutrients. So, keto does work for weight loss.1

Keto has also been found to possibly reduce the risk of certain kinds of cancer and has been evaluated as a possible treatment to be used in combination with chemotherapy.2 Many want to believe that keto is a cure for cancer, but there is simply not enough evidence to make that sort of claim

The ketogenic diet may be beneficial for brain health. It can help manage certain types of seizures. It may also protect against Alzheimer’s and dementia, which have been linked to blood sugar elevations.3

Cons of the Ketogenic Diet

After reading that list of pros, you probably think the keto diet is ideal. I am not going to lie, research is suggesting it could be beneficial for certain people and conditions. But, there are a few negative aspects to the ketogenic diet that I must present as well.

First, the keto diet is high in fat. Many people see this as an excuse to eat unlimited amounts of pork rinds and bacon. A high intake of saturated fat may increase cholesterol levels and risk of heart disease, although the research is not totally clear on the link between fat intake and heart disease risk.4

Keto, especially initially, may result in fatigue, constipation, and low blood sugar. People with heart disease, kidney disease, and diabetes should be cautious about trying a keto diet. It is not appropriate for pregnant or breastfeeding women or people with a history of eating disorders. There is also some concern that the lack of fiber may negatively alter gut microbes.

The Bottom Line on Keto

As a Registered Dietitian, you might be surprised to know that I am not against keto for the right person. For someone who needs to lose a large amount of weight, it can help them get motivated by losing a significant amount quickly. But, I don’t believe it is the “diet miracle” we have all been waiting for like some pro-keto people would lead you to believe.

That being said I don’t see it as a long-term way to eat. It is unrealistic and unhealthy to eliminate an entire food group FOREVER. Eventually, the carbohydrates are going to creep back in. And that means the weight will come back on. Keto, just like any other “diet” can help you gain motivation to start your weight loss journey, but you really need to ask yourself if life is worth living without an occasional piece of chocolate cake.

Yours in health-

Ana Reisdorf, MS, RD
IVL Community Registered Dietitian


  1. Bueno NB, de Melo IS, de Oliveira SL, da Rocha Ataide, T. Very-low-carbohydrate ketogenic diet v. low-fat diet for long-term weight loss: a meta-analysis of randomised controlled trials. Br J Nutr. 2013;110(7):1178-87.
  2. Allen BG, Bhatia SK, Anderson CM, et al. Ketogenic diets as an adjuvant cancer therapy: History and potential mechanism. Redox Biol. 2014;2:963–970.
  3. Gasior M, Rogawski MA, Hartman AL. Neuroprotective and disease-modifying effects of the ketogenic diet. Behav Pharmacol. 2006;17(5-6):431–439.
  4. Micha R & Mozaffarian D. Saturated Fat and Cardiometabolic Risk Factors, Coronary Heart Disease, Stroke, and Diabetes: a Fresh Look at the Evidence. 2010;45(10):893-905.