The ketogenic diet is a high-fat, moderate-protein, low-carb eating pattern that was originally developed to treat epileptic children by simulating a starvation state.
Instead of using glucose - from sugars and carbohydrates in the diet - as energy, a ketogenic diet forces the body to use ketones made by the liver from dietary fat.
Critics say the diet is high in fat, low in fiber, high in cholesterol, bad for gut health and unsuitable for women, especially before menopause, who need carbohydrates to make hormones such as progesterone.
But nutritional therapist Moira Newiss told the story Newsweek that she disagrees. After following the ketogenic diet for more than five years, she said it was perfectly suited for women.
"As someone who has suffered from severe burnout, chronic fatigue, and a number of mental health issues, a ketogenic diet has effectively fueled my brain and body so that all of my health issues have remained in remission," she said.
"Although I started to feel much better by eating low-carb and introducing stress management strategies, it wasn't until I went ketogenic that I regained 100 percent of my energy and mental clarity.
"Then I could climb mountains and race my bike, and get rid of all my brain fog."
One of the benefits of the ketogenic diet is that the body no longer has to rely on glucose for energy, so some people find that they have more stable energy levels - or, in Newiss's case, more energy overall.
"I tried it because I wanted to feel like a teenager again," she said. "I wanted to have boundless energy and feel full of vitality."
She said that in ketosis - when the liver produces ketones from fat for energy - the mitochondria in the cells can more efficiently make adenosine triphosphate (ATP): the fuel the body runs on, made from glucose or ketones.
Not everyone agrees that this process is more efficient with ketones than with glucose, but Newiss said it is, especially for the brain.
Newiss also said the ketogenic diet was more anti-inflammatory than glucose-based eating and produced more energy - all of which is disputed by some other nutritionists.
Another source of debate in the nutrition world, raised by Newiss, is the suitability of the ketogenic diet for women.
Some nutritionists, especially those who specialize in women's health, warn that certain hormones such as progesterone - an important female sex hormone along with estrogen - are dependent on carbohydrates.
"I think there are a lot of misunderstandings and myths about ketogenic diets," says Newiss. "One myth is that it will harm women's hormones, and that's exactly what it is: a myth."
She explained that research was still developing in that area, but that some evidence about women's thyroid glands - which produce hormones - suggested that the ketogenic diet could reduce the demand for hormones and increase thyroid sensitivity. can increase, which implies that the body has adapted to a ketogenic diet in no time. positive way.
"There are also other myths, such as a ketogenic diet negatively affecting the gut microbiome," says Newiss. "The gut microbiome is very complex and we have yet to discover and understand how all the different microbes work together and interact with the gut lining and our immune system.
"Yes, the ketogenic diet will change the gut microbiome, but it is constantly changing. This does not mean it is a bad thing."
Newiss said many of the studies that had shown the negative effects of ketogenic diets were flawed because they were conducted by feeding mice lots of poor-quality fats, high in omega-6, which is widely believed to be anti-inflammatory .
"Many studies using this type of ketogenic diet find that it promotes inflammation, which is not surprising!" she said. "Eating natural fats reduces inflammation."
Newiss recommended following a ketogenic diet consisting of fat from eggs, avocados, coconut, meat, dairy, nuts, seeds, fish and olive oil; proteins from meat, dairy and legumes; and fewer than 50 grams of carbohydrates, from low-starch vegetables, such as kale, and low-sugar fruits, such as berries.
She said many think ketogenic diets are poor in nutrients, but this was only true if a person was eating poorly; If followed properly, she said, it could provide enough nutrients.
Saturated fat is another major talking point when it comes to reasons to avoid a ketogenic diet, but Newiss said the evidence indicated "there is no scientific basis for demonizing saturated fats as a cause of heart disease."
This is an ongoing nutritional debate; Does saturated fat cause heart disease, or are sugar and ultra-processed foods really to blame?
"Even today, many people continue to think fat is the problem, despite mounting mountains of evidence that sugar and carbohydrates are likely the culprit," says Newiss.
"The concern around saturated fat had to do with cholesterol and the heart health hypothesis that cholesterol from saturated fat caused heart disease.
"Elevated total cholesterol is not associated with increased cardiovascular risk. Not only that, but cholesterol is vital to your health, especially as you age, and higher cholesterol levels are associated with longevity."
However, Newiss did say that ketogenic diets weren't for everyone, and she didn't recommend them for all her nutrition clients.
"I would always advise women to seek professional help before starting a ketogenic diet if they are taking medications," she said.
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