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As the popularity of the ketogenic diet continues to grow so does interest in how to optimize health while following this high-fat, low-carb eating plan.

Because the keto diet cuts out a number of food options, it’s a good idea to supplement with specific nutrients.

Not to mention, some supplements can help dieters reduce adverse effects of the keto flu and even enhance athletic performance when training on a low-carb diet.

Here are the best supplements to take on a keto diet.

1. Magnesium

Magnesium is a mineral that boosts energy, regulates blood sugar levels and supports your immune system (1).

Research suggests that due to magnesium-depleting medications, reliance on processed foods and other factors, a good portion of the population has or is at risk of developing a magnesium deficiency (2).

On a ketogenic diet, it may be even more difficult to meet your magnesium needs, as many magnesium-rich foods like beans and fruits are also high in carbs.

For these reasons, taking 200–400 mg of magnesium per day may be beneficial if you’re on a keto diet.

Supplementing with magnesium can help reduce muscle cramps, difficulty sleeping and irritability — all symptoms commonly experienced by those transitioning to a ketogenic diet (3, 4, 5).

Some of the most absorbable forms of magnesium include magnesium glycinate, magnesium gluconate and magnesium citrate.

If you wish to increase your magnesium intake through keto-friendly foods, focus on incorporating these low-carb, magnesium-rich options:

  • Spinach
  • Avocado
  • Swiss chard
  • Pumpkin seeds
  • Mackerel
Summary

Those following a ketogenic diet may be at a higher risk of developing a magnesium deficiency. Taking a magnesium supplement or eating more low-carb, magnesium-rich foods can help you meet your daily requirements.

2. MCT Oil

Medium-chain triglycerides, or MCTs, are a popular supplement among keto dieters.

They’re metabolized differently than long-chain triglycerides, the most common type of fat found in food.

MCTs are broken down by your liver and quickly enter your bloodstream where they can be used as a fuel source for your brain and muscles.

Coconut oil is one of the richest natural sources of MCTs, with about 17% of its fatty acids being in the form of MCTs with potential metabolic benefits (6).

However, taking MCT oil (made by isolating MCTs from coconut or palm oil) provides an even more concentrated dose of MCTs and can be helpful for those following a ketogenic diet.

Supplementing with MCT oil can help keto dieters since it can quickly up your fat intake, which increases ketone levels and helps you stay in ketosis (7).

It has also been shown to promote weight loss and increase feelings of fullness, which can be helpful for those using the ketogenic diet as a weight loss tool (8).

MCT oil can be easily added to shakes and smoothies or simply taken by the spoonful for a quick fat boost.

It’s a good idea to start with a small dose (1 teaspoon or 5 ml) of MCT oil to see how your body reacts before increasing to the suggested dosage listed on the supplement bottle.

MCT oil can cause symptoms like diarrhea and nausea in some people.

Summary

MCT oil is a type of rapidly digested fat that can be used to help ketogenic dieters boost fat intake and stay in ketosis.

3. Omega-3 Fatty Acids

Omega-3 fatty acid supplements, such as fish or krill oil, are rich in the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which benefit health in many ways.

EPA and DHA have been found to reduce inflammation, lower heart disease risk and prevent mental decline (9).

Western diets tend to be higher in omega-6 fatty acids (found in foods like vegetable oils and processed foods) and lower in omega-3s (found in fatty fish).

This imbalance can promote inflammation in the body and has been linked to an increase in many inflammatory diseases (10).

Omega-3 supplements can be particularly beneficial for people on ketogenic diets, as they can help maintain a healthy omega-3 to omega-6 ratio when following a high-fat diet.

What’s more, omega-3 supplements can maximize the ketogenic diet’s impact on overall health.

One study showed that people following a ketogenic diet who supplemented with omega-3 fatty acids from krill oil experienced greater decreases in triglycerides, insulin and inflammatory markers than those who did not (11).

When shopping for omega-3 supplements, choose a reputable brand that provides at least a combined 500 mg of EPA and DHA per 1,000 mg serving.

Those on blood-thinning medications should consult a doctor before taking omega-3 supplements, as they can increase your risk of bleeding by further thinning your blood (12).

To boost your intake of omega-3 fatty acids through keto-friendly foods, eat more salmon, sardines and anchovies.

Summary

Omega-3 fatty acid supplements can reduce inflammation, lower heart disease risk factors and help ensure a healthy balance of omega-3s to omega-6s.

4. Vitamin D

Having optimal levels of vitamin D is important for everyone’s health, including people following ketogenic diets.

The keto diet doesn’t necessarily put you at a higher risk of developing a vitamin D deficiency, but since vitamin D deficiency is common in general, supplementing with this vitamin is a good idea (13).

Vitamin D is important for many bodily functions, including facilitating the absorption of calcium, a nutrient that could be lacking on a ketogenic diet, especially in those who are lactose intolerant (14).

Vitamin D is also responsible for supporting your immune system, regulating cellular growth, promoting bone health and lowering inflammation in your body (15).

Since few foods are good sources of this important vitamin, many health professionals recommend vitamin D supplements to ensure proper intake.

Your doctor can run a blood test to determine if you’re deficient in vitamin D and help prescribe a proper dosage based on your needs.

Summary

Since vitamin D deficiency is common, it may be a good idea for people following the ketogenic diet to get their vitamin D levels checked and supplement accordingly.

5. Digestive Enzymes

One of the main complaints of those new to the ketogenic diet is that the high fat content of this eating pattern is tough on their digestive system.

Since the keto diet may consist of up to 75% fat, those used to consuming diets lower in fat can experience unpleasant gastrointestinal symptoms like nausea and diarrhea.

In addition, though the ketogenic diet is only moderate in protein, it may still be a higher amount than some people are used to, which can also cause digestive side effects.

If you’re experiencing digestive issues like nausea, diarrhea and bloating when transitioning to a ketogenic diet, a digestive enzyme blend that contains enzymes that break down fats (lipases) and proteins (proteases) may help optimize digestion.

What’s more, proteolytic enzymes, which are enzymes that help break down and digest protein, have been shown to reduce post-workout soreness, which can be a bonus for workout enthusiasts on a keto diet (16, 17).

Summary

Taking a digestive supplement that contains both protease and lipase enzymes, which break down protein and fat respectively, may help relieve digestive symptoms related to transitioning to a keto diet.

6. Exogenous Ketones

Exogenous ketones are ketones supplied through an external source, while endogenous ketones are the type produced naturally by your body through a process called ketogenesis.

Exogenous ketone supplements are commonly used by those following a ketogenic diet to increase blood ketone levels.

Aside from potentially helping you reach ketosis quicker, exogenous ketone supplements have been linked to other benefits as well.

For example, they have been shown to boost athletic performance, speed muscle recovery and decrease appetite (18, 19).

However, research on exogenous ketones is limited, and many experts argue that these supplements aren’t necessary for keto dieters.

Additionally, most of the studies on exogenous ketones used a more powerful type of exogenous ketones called ketone esters, not ketone salts, which is the most common form found in supplements available to consumers.

While some people may find these supplements helpful, more research is needed to establish their potential benefits and risks.

Summary

Exogenous ketones may help raise ketone levels, decrease appetite and increase athletic performance. However, more research is needed to establish the effectiveness of these supplements.

7. Greens Powder

Increasing vegetable intake is something that everyone should focus on.

Vegetables contain a wide variety of vitamins, minerals and powerful plant compounds that can fight inflammation, lower disease risk and help your body function at optimal levels.

Though not everyone following a keto diet is necessarily lacking in their vegetable intake, this eating plan does make it more difficult to consume enough plant foods.

A quick and easy way to boost your vegetable intake is by adding a greens powder to your supplement regimen.

Most greens powders contain a mixture of powdered plants like spinach, spirulina, chlorella, kale, broccoli, wheatgrass and more.

Greens powders can be added to drinks, shakes and smoothies, making them a convenient way to increase your intake of healthy produce.

Those following ketogenic diets can also focus on adding more whole-food, low-carb vegetables to their meals and snacks.

While it shouldn’t be used as a replacement for fresh produce, a well-balanced greens powder is an excellent and easy way for keto dieters to add a nutrient boost to their meal plan.

Summary

Greens powders contain powdered forms of healthy plants like spinach, spirulina and kale. They can provide a convenient source of nutrients to those following ketogenic diets.

8. Electrolyte Supplements or Mineral-Rich Foods

Focusing on adding minerals through diet is important for people following a ketogenic diet, especially when first switching to this way of eating.

The first weeks can be challenging as the body adapts to the very low number of carbs consumed.

Transitioning to a ketogenic diet results in increased water loss from the body (20).

Levels of sodium, potassium and magnesium can drop as well, leading to symptoms of the keto flu, such as headaches, muscle cramps and fatigue (21).

Additionally, athletes following a keto diet may experience even greater fluid and electrolyte losses through sweating (22).

Adding sodium through diet is the best strategy. Simply salting foods or sipping on a broth made with bouillon cubes should cover most people’s increased sodium needs.

Increasing your intake of potassium- and magnesium-rich foods can counteract losses of these important minerals, too.

Dark leafy greens, nuts, avocados and seeds are all keto-friendly foods that are high in both magnesium and potassium.

Electrolyte supplements containing sodium, potassium and magnesium are available as well. You can shop for electrolyte supplements on Amazon.

Summary

People following a ketogenic diet should focus on increasing their consumption of sodium, potassium and magnesium to prevent unpleasant symptoms like headache, muscle cramps and fatigue.

9. Supplements to Boost Athletic Performance

Athletes looking to boost performance while on a ketogenic diet may benefit from taking the following supplements:

  • Creatine monohydrate: Creatine monohydrate is an extensively researched dietary supplement that has been shown to promote muscle gain, improve exercise performance and increase strength (23, 24).
  • Caffeine: An extra cup of coffee or green tea can benefit athletic performance and boost energy levels, especially in athletes transitioning to a keto diet (25).
  • Branched-chain amino acids (BCAAs): Branched-chain amino acid supplements have been found to reduce exercise-related muscle damage, muscle soreness and fatigue during exercise (26, 27, 28).
  • HMB (beta-hydroxy beta-methylbutyrate): HMB may help decrease muscle loss and increase muscle mass, especially in those who are just beginning an exercise program or increasing the intensity of their workouts (29, 30).
  • Beta-alanine: Supplementing with the amino acid beta-alanine may help prevent fatigue and muscle burnout when following a ketogenic diet (31, 32).
Summary

Athletes following a ketogenic diet may benefit from certain supplements that preserve muscle mass, boost performance and prevent fatigue.

The Bottom Line

The high-fat, low-carb ketogenic diet is followed for various reasons, from promoting weight loss to boosting athletic performance.

Some supplements can make the transition to this way of eating easier and help reduce symptoms of the keto flu.

What’s more, many supplements can improve the nutritional value of a ketogenic diet plan and even enhance athletic performance.

Taking these supplements can help optimize nutrition and allow you to thrive while on a keto diet.