Diet fads come and go, but one that you’ve probably been hearing about for a while now is the Keto diet. What exactly is it, though? Is there more hype than actual results? While some people see benefits, others don’t, so how do you judge if it’s working?

The keto diet is not new. It was first used in the 1920s to treat kids with epilepsy. In fact, it’s still sometimes used for that. Studies have shown that somewhere been ⅓ – ⅔ of kids have 50% fewer seizures after six months on the regimen. This isn’t why most people are familiar with the keto diet, though. In recent years, it’s been gaining traction as a way to lose weight or fuel extreme endurance sports, such as marathon running and triathlons. Why is it being used for these purposes?

Keto is short for ketogenic. While it’s similar to Atkins and other diets that focus on low carbs, it doesn’t focus on protein as the replacement. Instead, the plan centers on fat. Essentially, you replace carbohydrates with fat. When you consume foods that contain carbohydrates, your body converts them to glucose (the body’s primary energy source). Since glucose is the simplest form of energy, it’s always used for energy before your body turns to stored fat for fuel.

When you reduce carbs, it puts your body into a metabolic state called ketosis, a normal metabolic process that occurs when the body doesn’t have enough glucose for energy. As a result, your body becomes incredibly efficient at burning fat for energy. Fat turns into ketones in the liver, and these are used to fuel the body in the absence of glucose. The thought is that by putting the body into ketosis, it’ll maximize fat loss. It’s important to note that it takes two to three weeks on the diet to start ketosis in the body.

Are there other health benefits?

Besides its fat-burning capabilities, one of the reasons the keto diet is used for weight loss is appetite suppression. Some evidence suggests that people feel less hungry and have fewer cravings. Studies have now shown that the diet can have benefits for a wide variety of different health conditions. The weight loss associated with the diet can help improve risk factors like body fat, HDL (good) cholesterol levels, and blood pressure; thus, it decreases your chances of heart disease.

It’s well documented that diabetes is characterized by changes in metabolism, high blood sugar, and impaired insulin function. Actually, one study found that the keto diet improved insulin sensitivity by 75%. Excess fat is closely linked to type 2 diabetes. Since the keto diet helps you lose fat, it reduces your chances of developing type 2 diabetes and metabolic syndrome.

Obviously, the benefits of the keto diet have been proven for epilepsy. Due to this success, it’s being researched to see if it has any beneficial impacts on other brain conditions, such as traumatic brain injuries, Alzheimer’s disease, and Parkinson’s disease. Two other areas also being looked into are cancer to slow tumor growth and polycystic ovary syndrome because of the diet’s ability to reduce insulin levels, which may play a vital role in the condition.

How does the keto diet compare to a “normal” diet?

The standard ketogenic diet (SKD) is a very low carb, moderate protein, and high-fat diet (contains 70% fat, 20% protein, and only 10% carbs). This is vastly different than the United States Department of Agriculture’s (USDA) dietary recommendations are 45 – 65% carbohydrates, 20 – 35% fat, and 10 – 35% protein. Data shows that the average man 20 or older consumes 46.4% of his daily calories from carbs, and the average woman older than 20 consumes 48.2% of her daily calories from carbs.

However, if you’re following the standard keto diet and consuming a total of 2,000 calories a day, this means no more than 200 of your calories (or 50 grams) should come from carbs, while 400 to 600 calories should come from protein and 1,200 to 1,600 should come from fat.

There are several versions of the keto diet. The cyclical ketogenic diet (CKD) involves periods of higher-carb refeeds, such as five ketogenic days followed by two high-carb days. The targeted ketogenic diet (TKD) allows you to add carbs around workouts. A high protein ketogenic diet is similar to a standard keto diet but includes more protein (the ratio is often 60% fat, 35% protein, and 5% carbs). It’s vital to note that only the standard and high protein ketogenic diets have been studied extensively.

While protein is part of the keto diet, it doesn’t typically discriminate between lean protein foods and protein sources high in saturated fat. Another concern with protein is that it can be converted into glucose if consumed in high amounts. This can slow your transition into ketosis. Some studies show that practicing intermittent fasting could help you enter ketosis faster. The most common method involves limiting food intake to around 8 hours per day and fasting for 16 hours.

How to follow the keto diet?

When starting the keto diet, it’s best to consume mainly whole, single-ingredient foods. It’s important to note that most fruits are restricted because of their naturally high carbohydrate content. Non-starchy vegetables, like leafy greens, should become a large part of your diet. Try to rotate vegetables and meat because each type provides different nutrients and health benefits. Adding fat-rich foods, such as avocado, nuts, and seeds, are essential because they provide you with unsaturated fats along with beneficial fiber. When cooking, plant-based oils, including extra virgin olive oil, coconut oil, and avocado oil, provide healthy fat. Besides the foods we just discussed, foods that are okay to consume on a keto diet are:

  • Protein: red meat, steak, ham, sausage, bacon, chicken, turkey, salmon, trout, tuna, shellfish, mackerel, and soybeans
  • Eggs: pastured or omega-3 whole eggs
  • Butter and cream: grass-fed butter and heavy cream
  • Cheese: unprocessed cheeses like cheddar, goat, cream, blue, or mozzarella
  • Nuts and seeds: almonds, walnuts, flaxseeds, pumpkin seeds, chia seeds, pistachios, sunflower seeds, and coconut (in moderation)
  • Avocados: whole avocados or freshly made guacamole
  • Low carb veggies: green veggies, tomatoes, onions, peppers, broccoli, cauliflower, cabbage, peppers, mushrooms, onions, and rhubarb
  • Condiments: salt, pepper, herbs, and spices
  • Fruits: berries (in moderation)

Any food that’s high in carbs should be limited. Here’s are some of the foods that you need to reduce or eliminate from your diet:

  • Sugary foods: soda, fruit juice, smoothies, cake, ice cream, candy
  • Grains or starches: wheat-based products, rice, pasta, cereal
  • Fruit: most of them, except small portions of berries
  • Beans or legumes: peas, kidney beans, lentils, chickpeas
  • Root vegetables and tubers: potatoes, sweet potatoes, carrots, parsnips
  • Low fat or diet products: low-fat mayonnaise, salad dressings, and condiments
  • Some condiments or sauces: barbecue sauce, honey mustard, teriyaki sauce, ketchup
  • Unhealthy fats: processed vegetable oils, mayonnaise
  • Alcohol: beer, wine, liquor, mixed drinks
  • Sugar-free diet foods: sugar-free candies, syrups, puddings, sweeteners, desserts
  • Processed foods: crackers, corn chips, and potato chips

Ways to get started

It might seem overwhelming to try to start a keto diet, but there are several tips that you can use to make it easier. The first step is familiarizing yourself with food labels and looking at the grams of fat, carbs, protein, and fiber. Another helpful tip is to plan out your meals in advance to help you save extra time throughout the week. You can use a ketogenic calculator to create a custom food plan.

The good news is many websites, food blogs, apps, and cookbooks offer keto-friendly recipes and meal ideas that you can use to build your own custom menu. Due to the diet’s popularity, some meal delivery services even offer keto-friendly options. To make it easy to stick to your diet when going to social gatherings or visiting family and friends, you may want to consider bringing your own food.

As far as restaurants go, many meals can be made keto-friendly. Try ordering meat or fish-based dish and replace any high-carb food with extra vegetables. Other options are egg-based meals or bun-less burgers you can add extra avocado, cheese, bacon, or eggs. For dessert, ask for a mixed cheese board or berries with cream. Definitely, minimize alcohol intake. If you do drink, choose low-carb options (vodka, tequila) and soda water as a mixer.

At least in the beginning, it’s important to eat until you’re full and avoid restricting calories too much. Usually, at first, a keto diet causes weight loss without intentional calorie restriction. After the first couple of months, you can eat carbs on special occasions. The key is to return to the diet immediately after.

How to know if you’re in ketosis?

One of the first questions people ask is how do you know when your body is in ketosis. There are blood, urine, and breath tests available. They measure the amount of ketones produced by your body. Also, specific symptoms can indicate that you’ve entered ketosis, including increased thirst, dry mouth, frequent urination, and decreased hunger or appetite.

Other considerations

While the keto diet doesn’t require including fitness in your routine, it’s crucial to increase your physical activity when you want to reduce or maintain a healthy body weight. If you’re not used to exercising, the transition to the keto diet may make sticking with your fitness routine a challenge at first. Experts recommend that if you feel your energy levels drop too much when starting the diet, slow down your reduction of carbs. Instead, reduce them gradually rather than all at once.

Another consideration is supplements. They aren’t required but might be helpful. MCT (medium-chain triglycerides) oil can be added to drinks or yogurt and provides energy, and helps increase ketone levels. Minerals, like added salt and others, can be helpful when starting due to shifts in water and mineral balance. Caffeine provides energy, increases fat loss, and boosts performance. Exogenous ketones are a supplement that may help raise the body’s ketone levels. Creatine has numerous benefits for health and performance, especially useful if you are combining a ketogenic diet with exercise). Whey protein is a plant-based protein that can increase your daily protein intake if needed.

What are the side effects?

Although the keto diet is safe for most healthy people, there may be some initial side effects while your body adapts to the lower amount of carbs, your body’s stored glucose begins depleting, and the body starts adapting to producing and utilizing ketones as energy. The main complaint is often referred to as the keto flu, and it typically lasts a couple of days. Symptoms include fatigue, headache, dizziness, sleep problems, cramps, nausea, diarrhea, constipation, and vomiting. Sometimes, digestion issues can linger for 3 – 4 weeks. If you’re constipated, try eating more high-fiber veggies.

Another way to lessen the effects is to transition onto a keto diet slowly. If you’re constantly tired, weak, or fatigued, you may not be in full ketosis or be utilizing fats and ketones efficiently. This is where a supplement like MCT oil or ketones may help.

Long-term concerns

Staying on the keto diet long-term may have some negative health effects, including low protein in the blood, extra fat in the liver, kidney stones, and micronutrient deficiencies, such as calcium, vitamin D, vitamin C, selenium, magnesium, phosphorous, folic acid, and other B vitamins. This is why eating a wide variety of vegetables, fruits, and grains is critical. Research shows that reliance on a diet rich in animal fats, especially saturated fats, and proteins may harm heart health because it can raise cholesterol levels.

Another concern is a medication used to treat type 2 diabetes, sodium-glucose cotransporter 2 (SGLT2) inhibitors, and the keto diet because it can increase the risk for diabetic ketoacidosis. Anyone taking this medication should avoid the keto diet. An additional concern for diabetics is the risk the keto diet poses to your kidneys because of the elevated ketones in the blood. Even those without diabetes need to be careful with their kidney function.

One of the biggest challenges of a keto diet may be long-term adherence because it’s challenging to stick to and maintain since it’s so restrictive. If you follow a strict diet for weight loss and then revert to old habits when the dietary changes are too restrictive, it leads to weight cycling or yo-yo dieting. This is associated with poorer cardiovascular health.

Some individuals are concerned about muscle loss. It’s important to point out that there’s a risk of losing some muscle on any diet. However, protein intake and high ketone levels may help minimize this, especially if you lift weights.

Some people notice that their urine or breath smells fruity. Both are common side effects. To help with your breath, try drinking naturally flavored water or chewing sugar-free gum. With so much fat to metabolize, the diet could make any existing liver conditions worse.

Literature from the National Lipid Associations found that for the first 2 – 6 months, there’s evidence that a very low-carbohydrate diet can help you lose more weight than the standard high-carbohydrate, low-fat diet. However, by 12 months, that advantage is essentially gone. So, the benefits of the keto diet may not be much different from any other diet plan if you look at it long-term.

Ketosis vs Ketoacidosis

People often confuse ketosis with ketoacidosis. Ketoacidosis is dangerous, but ketosis from a keto diet is usually fine for healthy people.

Ketoacidosis occurs in people with diabetes and is rapidly rising ketone levels. Insulin helps ferry glucose to our cells and muscles for energy. When there is an absence or not enough insulin (or the body is too resistant to insulin to allow it to do its job), the body can’t use glucose for fuel. Instead, the body resorts to burning stored fat for energy through ketosis, leading to a buildup of ketones in the body. This happens quickly, and as ketones accumulate in the bloodstream, they cause the blood to become more acidic.

The process by which ketones are formed on a keto diet is much slower, so not an emergency.

If you’re planning on trying the keto diet, consult with a dietitian or physician first to make sure that it’s safe for you to do so. Also, have your cholesterol levels regularly checked and replenish the fluids and sodium lost by increased urination and the severe restriction of carbohydrates. Remember, over the long haul, the diet isn’t going to magically alter your metabolism to where calories don’t matter anymore.