What you didn’t know about the keto diet

Jennifer Aniston keto diet

Thinking about jumping on this latest diet craze? You need to read this first

Beauty Crew Beauty Writer / April 26 2019

While the celeb-approved keto diet has been touted for its effectiveness in helping shed unwanted kilos and increase energy levels, there are also some not-so-known side effects that may surprise you.

We’re talking everything from bad breath and flu-like symptoms to loss of strength, gut health issues and even insulin resistance. Yep - it doesn’t sound like a good trade-off for some unwanted weight, right?

But before we get into some of the lesser known facts, it’s probably worth having a refresher on exactly what the keto, or ketogenic diet, actually involves.

What is the keto diet?

It’s basically a high-fat low-carb way of eating. It involves reducing or completely cutting out high carbohydrate foods from your diet - like wheat (bread, pasta, cereal), potatoes and rice. Instead, you should be eating foods that are high in fat and protein.

Exercise physiologist Drew Harrisberg says that on the keto diet around 75 per cent of your daily calories come from fat, 15 per cent from protein and less than 10 per cent from carbs. 

How does the keto diet work?

Harrisberg says, “When you drastically restrict carbs from your diet, your body converts fat to ketones, which are used as an alternative fuel source.” When ketones are built up in the blood, you are said to be in a state of ketosis. Being in this physiological state helps you lose weight, whilst maintaining muscle mass and keeping your hunger levels in check.

So, is keto bad for you? Or is keto healthy? If you’ve seen or heard a bad keto diet review and are sceptical about jumping on board this latest health craze, these are the pros and cons of the diet that you need to know before deciding if it’s right for you. 

Is the keto diet safe?

According to Harrisberg, although the keto diet may be used as an effective tool for short-term weight loss, it’s the long-term effects that are not yet fully known.

“To lose weight you need to achieve a calorie deficit i.e burn more calories than you store,” says Harrisberg. “If a ketogenic diet helps you to achieve a calorie deficit then it can be effective for weight loss. But short-term weight loss says nothing about long-term health, safety and sustainability.”

He says that while a shift towards a “real food approach” will generally result in improved health outcomes, there is currently no research behind the safety of the keto diet. “If you’re currently eating an unhealthy junk food diet then keto will be a step in the right direction, because it cuts out processed sugary garbage. But that doesn’t necessarily mean it’s the healthiest diet out there,” he says.

“Indeed, the keto diet can help you shed body fat fast, but when you look at the scientific evidence comparing isocaloric high-fat diets to low-fat diets (i.e calories are matched and controlled), weight loss is the same.”

“We don’t have enough long-term data and studies to indicate its safety yet. We know that the physiological state of ketosis has its pros and cons. We are not designed to live in a constant state of ketosis but rather fluctuate in and out. Just because some is good doesn’t mean more is better. For example, fasting is good for you and can induce ketosis, but if you don’t eat for long enough you’ll eventually die. Our body enters ketosis during periods of famine, therefore spending your lifetime in ketosis doesn’t seem optimal or healthy.”

When can the keto diet be dangerous?

According to Harrisberg, what kind of keto diet you do is an extremely important factor. While many opt for a whole foods approach and incorporate a well-balanced, nutrient-dense, low-carb diet, there are some alternate versions that involve eating processed meats, unhealthy fats and minimal vegetables, which could be bad for you in the long run. 

“If you’re drinking butter and coconut oil in your coffee, cooking with processed oils, eating bacon and processed meats, and not eating any fruit or veggies, then I can’t see how that is a healthy diet, even if you looked ripped on the outside,” says Harrisberg.

He says this modern, processed approach is one of the main reasons why keto is bad and people could be easily doing themselves more harm than good. “I worry about the long-term health implications of that type of ‘dirty’ keto diet. The evidence shows that diets high in saturated fats can increases cholesterol and increase your risk of developing heart disease, atherosclerosis, and stroke. The modern keto diet is also very low in fibre, which means your microbiome health (gut health) will not be optimal. The microbiome thrive on fibre from a diverse array of plant foods.” 

“It also restricts some of the healthiest foods known to be consumed by the longest living populations in human history with the lowest rates of chronic disease i.e the blue zones. By completely restricting things like starchy vegetables, fruit, legumes and wholegrains, you’re not aligning your way of eating with the healthiest populations that we know of.”

“The modern keto diet is highly processed and lacking real whole food. If you’re eating a real-food, mostly plant-based ‘clean’ keto diet rich in healthy fats, then I think it is safer than the dirty modern (mostly carnivore-style, meat heavy) keto diet, which is rich in saturated fat and lacking micronutrients from vegetables, legumes, and fruit.”

What are some common side effects of a keto diet?

Some other side effects include, “keto breath (acetone breath), loss of strength and power at maximal intensities, keto flu (flu-like symptoms during first few weeks of transition), carb intolerance, insulin resistance, some people experience increased cholesterol (although some people experience reduction in cholesterol), gut issues due to lack of fibre, and constipation.”

“In my personal case, after two months on a keto diet I became significantly insulin resistant,” reveals Harrisberg. “My blood sugar control and my insulin-to-carb ratio was the worst it has ever been. The science is clear that high fat diets impair glucose tolerance and worsen insulin sensitivity. If you’re happy to never eat carbs again then this isn’t necessarily a problem, but if you reintroduce carbs your body will not be able to tolerate them optimally."

Harrisberg says even if the keto diet does help you to achieve rapid weight loss, it’s not sustainable, and “if you can’t stick to it for your lifetime you’ll just rebound and gain the weight back (or more).”

When can the keto diet be helpful? 

“Physiological ketosis does have therapeutic benefits for people living with severe epilepsy. In fact, it has been shown to be more effective for managing the symptoms of epilepsy than pharmaceutical interventions,” says Harrisberg.

Ketosis is also known to be great for increasing satiation - making it easy to go long periods without eating. It also works as a tool for improving cognition, focus and concentration, while also contributing to a stable mood and energy level.

However, Harrisberg stresses that all of these benefits can be achieved on a strictly whole food diet too, and a keto diet is not your only option. “You can achieve ketosis by fasting or even doing a mostly plant-based keto diet. I have concerns with the modern keto diet because it’s very high in saturated fat and I don’t think bacon, eggs, butter and coconut oil should make the bulk of your daily calories, especially when they’re replacing known healthy foods like fibre-rich, nutrient-dense, and antioxidant-rich fruit, legumes and starchy vegetables.”

Looking for more info on this latest diet craze? Check out our article on what you can and can’t eat on the keto diet.

What do you think of the keto diet? Have you tried it before? Let us know about your experience in the comment section below.

Main image credit: Getty

Erin Docherty is a Beauty Writer for BEAUTYcrew and a Grooming Writer for Men's Health magazine. She has a keen interest in cosmeceutical skin care and is currently working on minimising her 9-step skin care routine – because ain’t nobody got time for that. When she’s not writing about the latest beauty news, or applying copious amounts of serum, you can find her spending all her money in Sephora.