Everything You Need to Know About the Ketogenic Diet

Niha Zubair, Arivale Clinical Research Scientist, PhD
Niha Zubair
Arivale Clinical Research Scientist, PhD

From wellness blogs to social media, “going keto” seems to be taking over. What is the ketogenic diet? And more importantly, does it work? Let’s take a look.

What is the ketogenic diet?

In short, the ketogenic diet is a primarily composed of fats, with modest amounts of protein, and an extremely limited amount of carbohydrates. How much fat? On the diet, you’re supposed to get anywhere from 60 to 90 percent of your calories from dietary fat.

Generally, our bodies use carbohydrates as their main source of energy. After our bodies turn carbs into glucose, it’s either used immediately or stored as glycogen in the liver and muscle tissue.

When you deprive the body of carbs, it starts to use the glycogen in the liver for energy. Eventually, though, the liver runs out of glycogen, and another backup source of energy is needed. When this happens, the body enters a state of ketosis, where it starts to use fat as energy rather than storing it in the body.

This state of ketosis is thought by some to lead to many health benefits, including weight loss, lowering cholesterol, and maintaining blood sugars.

History of the Ketogenic Diet

Though currently trendy, the ketogenic diet is hardly new, and it has quite an interesting history.

The ketogenic diet was developed in the early 1920s to control seizure activity in children with epilepsy. It was the primary treatment for epilepsy until the invention of anti-seizure medications in the 1940s. The ketogenic diet is still used today to help children and adults who don’t respond well to anti-seizure medications, though it’s still unclear exactly how it helps prevent seizures.

Benefits of the Ketogenic Diet

Now comes the big question. Is the ketogenic diet actually good for you? While there are certainly risks with the ketogenic diet (which we’ll get into later), there are also some interesting, though relatively small, benefits.

Weight Loss

In the wellness space, going “keto” usually means going on a weight loss diet. Despite the incredibly high-fat content, research shows ketogenic diets may actually be effective for short-term weight loss, although results are fairly modest.

For example, researchers found people who are obese lost roughly two more pounds after a year on a ketogenic diet than those following a low-fat diet.

However, when you keep in mind how difficult the ketogenic diet is to follow perfectly, those two extra pounds might not be good enough reason to stick with it long-term. Furthermore, depending on your genetics, you may have a higher risk for weight gain on high-fat diets than other people, making the ketogenic diet a problematic choice for weight loss.

Blood Sugar

The majority of research demonstrates that short-term ketogenic diets improve glycemic control, or the ability to maintain normal blood sugar levels, in people who are obese or have type 2 diabetes.

Some studies demonstrated people following the ketogenic diet showed greater improvement in maintaining normal blood sugars than those following higher carbohydrate diets. This suggests that the ketogenic diet may have some short-term advantage over other diets when it comes to controlling blood sugar, though long-term effects remain unknown.

Cholesterol

The ketogenic diet also shows promise when it comes to blood lipids like cholesterol.

Though research on ketogenic diets and lipid levels is limited and typically in the context of weight loss for people who are obese, current evidence suggests ketogenic diets, in comparison to higher carbohydrate diets, modestly improve triglyceride and HDL cholesterol levels. (HDL is considered the “good” kind of cholesterol, while LDL is considered the more “harmful” kind of cholesterol.)

Risks of the Ketogenic Diet

While there may be some short-term benefits of a ketogenic diet, there are still many concerns from physicians and nutritionists about the long-term impact of such a restrictive and extreme diet.

Kidney Damage

Our kidneys can have trouble eliminating the waste products from protein metabolism; therefore, a high protein diet may worsen kidney function (especially in people with kidney disease). Although a ketogenic diet is not necessarily high in protein, in practice it is difficult to eliminate carbohydrates without increasing protein significantly—so most keto diets are high protein as well as high fat.

Some research in mice and humans suggests the possibility of kidney damage from high protein and ketogenic diets. On the other hand, some studies suggest that a ketogenic diet does not affect or may possibly improve kidney function. Given the inconsistency of the evidence, people with kidney-related medical conditions, including people with diabetes and kidney transplant patients, should be cautious here.

Nutritional Deficiencies

The ketogenic diet may increase the risk for nutritional deficiencies, especially when used long-term.

Remember, the ketogenic diet is extremely restrictive. Because it virtually eliminates carbohydrates—including fruits, whole grains, and starchy vegetables—it’s not surprising that it can lead to vitamin and mineral deficiencies. One study saw deficiencies—specifically in vitamins A, E, and magnesium—in children following the ketogenic diet for 12 months. Other nutritional deficiencies that could potentially occur from a ketogenic diet include folate, vitamin C, vitamin K, potassium, carotenoids, and flavonoids.

Other Side Effects

The ketogenic diet can also present shorter-term side effects including constipation, dehydration, fatigue, and nausea. These side effects occurred more commonly in those on the ketogenic diet than a higher carbohydrate weight loss diet. In addition, eliminating most of the fiber from the diet could create a cascade of problems, including adverse effects on the gut microbiome, which could have long-term negative health consequences.

Arivale’s Take

It’s really important to note that the research around benefits is based on people who followed the ketogenic perfectly, and doing that is a huge challenge. Keeping your body in a state of ketosis requires extreme vigilance and a sharp and consistent break from typical dietary habits.

The largest meta-analysis on ketogenic diets to date found that very few people actually follow it consistently. At the end of the follow-up period in most studies, individuals were consuming more carbohydrates than the ketogenic protocol allowed.

Arivale doesn’t recommend ketogenic diets because of the many potential concerns and lack of scientific research on the long-term effects of the diet. In general, if you decide to follow a ketogenic diet, you should do so only for a brief time and under close medical supervision. If you’re interested in the ketogenic diet, we recommend discussing the advantages and disadvantages with your healthcare provider.

Further Reading

References


 

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