Photo: Ivan Samkov

How long until the keto diet starts working?

It takes two to three weeks on the diet to start fat burning (ketosis) in the body. So, don't expect instant results. Some studies have shown that adhering to low- or very-low-carbohydrate ketogenic diets helps people lose weight.

mayoclinic.org - Is the keto diet for you? A Mayo expert weighs in

How long does it take to quit carbs?

Days 5 to 14: Reward Yourself Of course, everyone's experience is different. Some people will take longer to feel the benefits but by the end of...

Last updated Sep 19, 2019

Can I take magnesium while fasting?

Can You Take Magnesium During A Fast? The short answer: Yes—taking magnesium will not break a fast, and supplementing with electrolytes, in...

Last updated Aug 31, 2022

Promotion

Is the keto diet for you? A Mayo expert weighs in The ketogenic diet is all about eating the right foods in the right proportions. When you get it right, it'll trigger your body to start burning stored fat.

The ketogenic diet gets headlines because celebs like Kim Kardashian West and LeBron James have championed it for weight loss. But what exactly is it, and does the science support the hype?

The ketogenic — or keto — diet emphasizes high-fat foods and severely restricts carbohydrates. In fact, about 60% to 80% of calories should come from fat, according to Jason Ewoldt, RDN, LD, a wellness dietitian at Mayo Clinic Healthy Living Program (HLP). He notes that a true keto diet also includes only moderate amounts of protein, and less than 50 grams of carbohydrates a day. Interestingly, the keto diet has been around for a long time. Doctors first started using it, Ewoldt says, in the 1920s to treat kids with epilepsy, and it's still sometimes used for that. But today, it is gaining traction for weight loss or to fuel extreme endurance sports like marathon running and triathlons.

How does the keto diet work?

As Ewoldt explains, a typical American diet consists of 50% or more carbohydrates, which convert to glucose in the body. Your cells burn that glucose as fuel. But when you switch to a very high-fat, low-carb diet, your body, by necessity, shifts away from glucose and instead uses fatty acids and ketone bodies for energy. This process is called ketosis — hence the diet's name.

What foods can you eat?

Ewoldt says nuts, seeds, full-fat cheese and other dairy products, plain Greek yogurt, nonstarchy and fibrous vegetables, oils, along with smaller amounts of meats, eggs and fish, become keto diet mainstays. You'll need to sharply limit carbohydrates, including bread and baked goods, sweets, pasta, breakfast cereals, starchy vegetables like potatoes, sweet potatoes, corn and peas, beans, fruit, and beer. Thirsty? Reach for the water bottle, or enjoy some sparking water. Unsweetened coffee and tea also are allowed. Minimize alcohol intake; if you do drink, choose low-carb options (vodka, tequila) and soda water as a mixer.

Does it really work for weight loss?

Yes — but that answer comes with a qualifier. It takes two to three weeks on the diet to start fat burning (ketosis) in the body. So, don't expect instant results. Some studies have shown that adhering to low- or very-low-carbohydrate ketogenic diets helps people lose weight. However, long term there is little difference between a ketogenic diet and a higher carbohydrate diet. Ewoldt adds a cautionary note: "This is a very restrictive diet that's tough to follow. The average person is not going to keep doing this long term. Also, because the saturated fat content is high, coupled with limited amounts of fruits, vegetables and whole grains, it is not optimal for health."

What sweetener knocks you out of ketosis?

Dates, date syrup, honey, maple, agave, yacon and blackstrap molasses are commonly cited as being healthy sweeteners. While they are naturally...

Last updated Jun 15, 2020

What happens to cooked tomatoes?

Antioxidant levels in the heated tomatoes increased by 28, 34 and 62 per cent, respectively. While the antioxidant activity in tomatoes is enhanced...

Last updated Oct 23, 2018

Promotion

Why do some athletes follow a keto diet?

Ewoldt explains it like this: "Following a balanced diet that includes carbohydrates, a trained athlete can store about 2,500 calories of glucose, the preferred source of energy. But this same athlete has around 40,000 calories of fat available." The idea is that by switching to a high-fat diet the body will adapt from using carbohydrates for energy to using fat. Because a vastly greater amount of fat is available, that would, in theory, keep endurance athletes like marathon runners or triathletes going longer. However, athletes do need some carbohydrate to use along with fat for energy. Ewoldt adds that the process of adapting your body from glucose-burning to fat-burning can take several weeks to months. There is a problem with information submitted for this request. Review/update the information highlighted below and resubmit the form. From Mayo Clinic to your inbox Sign up for free, and stay up to date on research advancements, health tips and current health topics, like COVID-19, plus expertise on managing health. Email ErrorEmail field is required ErrorInclude a valid email address Learn more about Mayo Clinic’s use of data. To provide you with the most relevant and helpful information, and understand which information is beneficial, we may combine your email and website usage information with other information we have about you. If you are a Mayo Clinic patient, this could include protected health information. If we combine this information with your protected health information, we will treat all of that information as protected health information and will only use or disclose that information as set forth in our notice of privacy practices. You may opt-out of email communications at any time by clicking on the unsubscribe link in the e-mail. Subscribe! Thank you for subscribing! You'll soon start receiving the latest Mayo Clinic health information you requested in your inbox. Sorry something went wrong with your subscription Please, try again in a couple of minutes Retry

mayoclinic.org - Is the keto diet for you? A Mayo expert weighs in

Is dark chocolate keto friendly?

While 1 ounce (28 grams) of high quality dark chocolate can fit into a keto diet, a larger serving will likely exceed your limit. Dark chocolate...

Last updated Mar 3, 2018

Why you shouldn't do keto long-term?

They found that people who follow such diets have a significantly increased risk of developing heart disease, LDL cholesterol buildup, kidney...

Last updated Sep 11, 2019

Promotion

Do you lose inches before pounds?

It's possible to gain muscle and reduce body fat without actually seeing a change in your weight. This happens when you lose body fat while gaining...

Last updated Jan 17, 2022

Promotion

How did I gain 2 pounds overnight on keto?

The Bottom line Sudden weight gain on keto may stem from increased water retention to even gaining muscle. Unless you're overeating, there's a good...

Last updated Aug 18, 2019