Fact-Checking Health Trends: Keto Diet

Every year, it seems another fad diet comes along. One of the more popular ones right now is the ketogenic or “keto” diet. Like many fad diets, it promises fast weight loss and ease of burning fat. Its appeal has spawned a whole mini-industry of keto-related products, from cookbooks to snacks. But is it really all that effective? And is it dangerous? Here are the facts about the keto diet.

What is the Keto Diet?

You may be surprised to know that the keto diet has actually been around for nearly a century. It was a special diet developed in the 1920s to treat seizures in children with epilepsy. However, doctors largely abandoned it (except for the most difficult cases) when newer and more effective anticonvulsant drugs were developed in the 1970s. Only until recently did the public start having an interest in the diet again as a weight loss method. A number of diets based on it, such as the Atkins diet, have since sprung up.

The keto diet is a high fat, moderate protein, and very low carbohydrate diet. The ratio of the three can vary (because of individual differences, for instance), but it’s generally around a 4:1 ratio of fat calories to calories from protein and carbohydrates, with carbohydrates making up around 5% (less than 50 g/day).

Normally, the body uses glucose for energy. But on the keto diet, the body runs out of glucose and starts using an alternative energy pathway where it starts breaking down fat and protein for energy. The process (called ketosis, where the diet gets its name from), produces ketone bodies which serve as a replacement for glucose.

For reasons not entirely understood, when the brain uses ketone bodies as energy instead of glucose, it decreases the incidence of epileptic seizures. The evidence for this effect is so strong that the keto diet is still a mainstream treatment for seizures in children.

The Keto Diet for Weight Loss

While the evidence for the keto diet’s effectiveness for seizures is strong, the evidence for its effectiveness for weight loss is much more ambiguous at best. A lot of its popularity came from the “carbohydrate-insulin hypothesis”. It proposed that carbohydrates are more fattening than any other macronutrient because it increases insulin and therefore causes fat to accumulate. It also claimed that a low-carb diet would have a metabolic advantage (burning about an additional 400-600 calories/day) compared to other diets.

To prove the hypothesis, one of its advocates, Gary Taubes, co-founded the Nutrition Science Initiative in 2012 to conduct a huge, rigorous experiment on it. But as it turned out, not only was the hypothesis baseless in terms of human biology, it was debunked by the experiment as noted by Kevin Hall in 2017 (the National Institutes of Health (NIH) researcher who designed it). The experiment found that there wasn’t any significant difference in fat loss between a ketogenic diet (5% carbohydrate) and a regular diet with the same calories.

Some studies on the keto diet still pop up occasionally claiming that it’s better for weight loss than other diets. But many of them are somewhat misleading. The body stores glucose with a lot of water (3 g of water per gram of glycogen), so emptying your glucose reserves will make you lose that water. As a result, weight loss is generally faster in the beginning because a lot of it’s water weight.

Many of the studies are short term (usually half a year or less). So, this fast weight loss would make it seem like the keto diet is more effective. But, as many dieters know, water weight loss is useless since it comes right back. Analyses of studies that last more than one year show that the difference in weight loss between the keto diet and other diets is pretty small (on the order of less than 1 kg).

Issues with the Keto Diet

With so many people going on social media and saying how the keto diet helped them get rid of extra weight, you might be thinking that it’s pretty safe and easy. But it’s actually a lot more complicated than it looks. It’s good for epileptic children. There’s also some evidence it can help obese people control their weight and diabetics control their blood sugar. But for average people, it may be more harmful than good. As I mentioned before, the keto diet is just about as effective as other diets. So, many of the risks inherent to the keto diet are entirely unnecessary. Here are the main issues with the keto diet:

Adherence

Any diet that makes you eat less calories than you need will help you lose weight. The main thing is that you need to stick with it. It’s probably the main reason why fad diets almost never work. They give the impression that if you follow the diet and maybe lose a few pounds, you can just go back to the way you were eating before, and everything will be fine. Dieting is only one part of losing weight and staying healthy (the other is exercise), and changing your diet is a permanent commitment. It’s to prevent that extra weight from coming back. That’s why picking a diet you can follow easily is key to adhering to it.

The keto diet, however, is incredibly difficult to follow. Any deviation from its strict macronutrient ratio can make your body go out of ketosis. In fact, even something as simple as one apple can do it.

The average person can only stay on it for about half a year (verified by urine ketone levels) before quitting. I can see why. My dieting plan consists of simply eating balanced meals and counting calories. Now if I had to count calories AND analyze the macronutrient ratio of every single thing I ate AND make sure that I was getting enough calories from fat while staying below the thresholds for protein and carbohydrates every day, I’d go crazy. As obesity researcher puts it, only the small minority of people who manage to stick with the diet and get good results from it are the ones boasting on the Internet about how easy and effective it is.

Low Nutrition

As you might guess, the keto diet puts a huge limit on what you can even eat. It’s so limiting that people on the diet for medical reasons need to have a dietician monitor everything they eat. Grain products (including whole grains), most fruit, and starchy vegetables are pretty much forbidden. Unfortunately, those foods have lots of nutrients that are hard to find elsewhere. These include the B vitamins, calcium, vitamin D, and dietary fiber.

High Fat

Well obviously a diet that makes you eat a lot of fat is going to be high in fat. Proponents of the keto diet often say that eating fat doesn’t make you fat. Technically it’s true, but it’s misleading. Eating fat (or protein and carbohydrates for that matter) isn’t the reason people get fat. Eating too much is. But the main problem with that claim is it misses the point entirely.

When you’re eating high amounts of fat, a lot of it is likely to be saturated fat. The reason why health organizations like the World Health Organization (WHO) and the American Heart Association (AHA) recommend that less than 10% of your calories come from saturated fat isn’t mainly because of weight gain. It’s because saturated fat increases LDL levels, which increases your risk of various cardiovascular diseases. In fact, they recommend the opposite of the keto diet: eating a high-fiber, low-fat diet, which is high in “good” carbs.

Some advocates of the keto diet say that you can just make sure that you eat mostly unsaturated fats. But not only does that make the diet even more restrictive, most people either don’t know about this distinction or don’t care. Many of the keto diet plans I see floating around the Internet recommend fatty red meats, cheese, butter, and coconut oil. All of these are very high in saturated fat.

Expensive

Because the keto diet is so restrictive, you’d probably need to start eating many different and likely unfamiliar foods. Unfortunately, many of the foods that keto dieters recommend, like berries, salmon, and avocados, are quite expensive. For some, red meat is also too expensive to eat regularly. These expenses may lead some people to seek out cheaper, less healthy foods like processed meats.

Adverse Health Effects

Ketosis is not a normal state for the human body. Not even for the Inuit, who live on a high-fat diet. They have mutations that prevent them from overproducing ketone bodies. This unnatural state along with the various nutritional deficiencies from the keto diet have the potential to cause many side effects. Here are some of them:

halitosis (bad breath) from the buildup of acetone (a ketone body)
constipation (likely from low dietary fiber)
nausea
headache
vomiting
gastrointestinal problems (likely due to low dietary fiber changing the bacterial population in the gut)
abnormal odors from the vagina (due to changes in vaginal pH which leads to changes in the bacterial population living there)
general weakness/lower athletic performance (type I “slow twitch” muscles use all three macronutrients for energy, while type II “fast-twitch” muscles primarily use glucose)
stunted growth (in children)
increased risk of osteoporosis (more calcium lost in urine)
prurigo pigmentosa (painful, itchy rashes that can leave permanent marks on the skin and can only be stopped by going off ketosis)
increased risk of kidney stones (from more uric acid)
increased risk of gout (from more uric acid)
can escalate to ketoacidosis (a life-threatening condition that changes the pH of blood when the body’s mechanisms to limit ketone production fail)

Some of these problems are so common that people on the diet have given them annoyingly cutesy names like keto flu, keto breath, keto crotch, and keto rash. Seriously, these names don’t change the fact that they’re still real health problems. You shouldn’t take them lightly. In fact, people with liver, pancreas, or kidney problems shouldn’t even try the keto diet.

Recent analyses show that these side effects could have real consequences down the line. One analysis that looked at 24,825 people in the US for more than a decade showed that the bottom 25% of people in terms of carb consumption had a 32% higher risk of death (any cause) than the highest carb eaters. It also found that low-carb eaters were 51% more likely to die from coronary heart disease and 35% more likely to die from cancer relative to people in the top 25% of carb consumption. Another analysis looking at 447,506 people worldwide found that low-carb dieters had 15% higher risk of death overall.

Better Alternatives

With all the problems and risks involved with the keto diet, it’s no wonder that fans recommend “cycling” the diet with another diet (usually the Mediterranean diet). But really, why bother? Why not just stick with another healthier diet consistently? All diets perform about the same in the long run in terms of weight loss if you stick with them. And the keto diet is among the worst diets in terms of health, ease of following it, and long-term weight loss success. The two diets that are consistently among the top of the rankings are the DASH (Dietary Approaches to Stop Hypertension) diet and the Mediterranean diet.

DASH Diet

This diet, as its name suggests, is mainly for lowering hypertension (high blood pressure). But it’s great for general health, too. It recommends eating plenty of fruits and vegetables, whole grains, lean protein, and low-fat dairy. It also recommends cutting down on foods that are high in saturated fat (fatty meats, full-fat dairy foods and tropical oils like coconut oil) and refined sugars. A key part of the diet is limiting sodium to about 2,300 mg/day and eventually lowering it to 1,500 mg/day. It’s a balanced diet that’s also easy to follow long-term.

Mediterranean Diet

This diet’s been in the news plenty of times for having all sorts of health benefits. These include longer life, stronger bones, better heart health, and a lower risk of certain brain diseases, certain cancers, diabetes, and high blood pressure. It emphasizes plant-based cooking and recommends plenty of fruits and vegetables, whole grains, beans, seeds, nuts, fish, and extra virgin olive oil. It cuts down on refined sugars and flour, meats (to some degree compared to typical Western portions), and any fats other than olive oil. Like the DASH diet, it’s also balanced and easy to follow.

Conclusion

While the keto diet may help some people with weight loss, it’s really more of a backup medical treatment for people with epilepsy or diabetes. It’s hard to follow, unhealthy, and completely unnecessary for losing weight. People these days are too obsessed with losing weight and, in the process, miss the bigger picture of staying healthy. It’s one of the main reasons why fad diets, keep popping up and catching on. Many of these are just old, failed concepts rebranded as new diets with new promises. The keto diet is no exception.