We’ve already discussed the keto diet and what it can do for you, but with the huge amount of misinformation that’s out there, we’re going to answer some of the most common questions that people have about the keto diet.

Today’s “frequently asked questions” article will cover some of the discussions that we see online – and we intend to clear up any problems you might have. Curiosity about a new diet makes total sense, and the discussions online leave a lot to be desired!

1. Who should use a ketogenic diet?

The main beneficiaries of a keto diet are women, endurance athletes, those with a concern for insulin sensitivity/diabetes, or simply anyone who struggles to control their carb intake.

If you fit into any of the categories mentioned above, the ketogenic diet is probably for you. Alternatively, you’ll want to avoid this diet if you’re looking solely to build muscle, work in a power sport, or simply don’t need the benefits of endurance or carb control.

2. What is ketosis?

Ketosis is simply the state your body is in when it has run out of a supply of carbs. This can happen because you’re not eating carbs or because you’re depleted from exercise.

This is the point for keto-adaptation: ketosis is almost inevitable in high-level endurance, so you should probably get really good at it. Nutritional ketosis – the kind that happens when you restrict carb intake – makes you better at exercise-induced ketosis.

Simply put, ketosis is the process of burning fat for fuel. The more you do it, the better you get at it.

3. How do I know I’m in ketosis?

This is pretty hard to tell, but that’s not just ketosis. How do you know if you’re using carbs for fuel right now? The inner workings of your body are a bit of a mystery to your conscious mind.

For the most part, you won’t need to worry about whether or not you’re in ketosis. If you’re sticking to the diet and you’re seeing changes in your performance, you’re probably in ketosis.

However, there are a few symptoms you can use to tell if your body is in a ketogenic state:

• Acetate-breath (very distinct—you’ll know it when you get there)
• Increased urination
• Improved endurance performance
• Reduced fatigue on a very-low-carb diet

The reality is that you don’t need to worry so much. Stick with it and be patient – you’ll adapt slowly, and the process isn’t just as simple as yes or no. Ketosis and keto-adaptation are slow, and you don’t need to be in ketosis 24/7 to keto-adapt. Just stick with the diet. However, if you’re one of those people that just can’t deal with the not knowing, there are test strips that you can order that will tell you if you’re in ketosis when you pee on them.

4. How long does it take to keto-adapt?

Keto-adaptation starts almost as soon as you’re out of carbs, and we’re not really sure when it peaks. You can see some signs of keto-adaptation within a week, while there are benefits to a 3-month keto-adaptation process.

The reality is that the human body adapts beautifully to its environment. If you remain on a keto diet for months or years, you’ll get more efficient at it.

We can say that you’ll reach the big positive effects mentioned above within about 3 months – as that’s the length of the most authoritative and important studies. There will some variation person-to-person, but this is a good general rule of thumb.

5. What type of exercise should I do on a keto diet?

Lots of endurance, not so much high-effort strength.

The keto diet doesn’t stop you from doing anything, and it won’t really matter too much to the average person. However, it does favor sub-maximal output for a longer duration. This means your ability to produce maximum force goes down, but your ability to produce lower force for more repetitions/time goes way up.

Obviously, this comes with the fact that your needs – be they endurance or fat loss – should determine your exercise. If you’re trying to maintain muscle on a ketogenic diet, you’ll want to include weight training in the sub-maximal and “stimulating” range. This is roughly in the 4-6 rep range (for several sets) that forces a slow bar speed. We might say that a rate of perceived exhaustion of 8 to 10 is ideal.

6. Do I need to count calories?

Yes.

You can’t lose weight by eating more than you use – even if you’re on a ketogenic diet. If you can, you’re dealing with a very serious metabolic problem. If you’re like most other people though, a calorie is still a calorie on this diet or any other.

You might not need to count calories all the time if a ketogenic diet accidentally reduces your calories to a fat-burning number, but you do need to eat less than you use. The ketogenic diet only really works if you’re at a deficit, as it relies on the burning of body fat rather than glycogen.

Keep an eye on your calories if you’re not losing weight or if you’re stalling. Your calorie needs change as you lose weight, so you’ll want to adapt fairly often. If you’re struggling, you should use an online TDEE calculator/calorie-tracker to provide some clarity.

Once you’ve been doing this for a while though, you’ll probably get to the point where you don’t need to track them anymore; you’ll just know what you need to eat. So we’re not talking a lifelong sentence of counting calories, people.  Very important when you’re beginning though, so pay attention.

7. What are macros?

Macronutrients – Protein, Carbohydrates and Dietary Fats – are the most important and common nutrients in food. They make up the vast majority of calories in your food, and their balance has some profound effects on how your body works. 

To simplify, protein is used for the creation and repair of tissues, carbohydrates are short-term energy, and fats are long-term energy stores. The way you balance these in your diet is important for keto, because you need to limit protein intake to adequate levels, restrict carbs, and increase your fat intake.

8. How many carbs can I have on a ketogenic diet?

The most important research suggests that keto-adaptation is optimal at around 30g of carbs a day. This does not include fiber, which is technically a carb but is not digested and therefore doesn’t produce an insulin response.

If you’re a significantly larger (in terms of musculature) or smaller human than average, you may need to adapt this. We say that roughly 5-7.5% of your dietary calories should be from carbs. This is a relatively safe bet, but again will vary some person-to-person.

9. How much protein can I have?

As mentioned above, you’ll need to restrict your protein consumption.

You can’t have too much protein on a keto diet or you’ll knock yourself out of ketosis. Same as with too many carbs. This happens for a few reasons – most of them are quite complicated – but the simplest explanation is that you’re likely to convert them into glycogen if you have a huge surplus.

This is one of the many reasons why a ketogenic diet is a weight-loss diet rather than a muscle-building one.

10. Will eating fat make me fat?

No.

Dietary fats and body fat are not the same thing, even though they both fall under the term “fat”. The word fat, used in this context, is a chemical umbrella term, and you won’t get fat just from eating a high-fat diet. You’d need to overeat on calories to produce that kind of change. Remember: calories are calories. Too many calories equals gaining fat.

Fats do contain 9 calories per gram compared to the 4 calories you’d find in a gram of carbohydrate or protein, so it can be easy to overeat. Make sure you track your calorie intake for a little while at the start of the diet just to get an idea of how much you’re eating.

11. Is the keto diet safe?

For most people, the ketogenic diet is absolutely safe, and there are very few side effects associated with it. While there may be some initial feelings of tiredness, fatigue or “keto flu,” these symptoms are temporary and will usually disappear as you adapt to relying on fats.

There are very few reasons you’d have health problems on a ketogenic diet. At-risk groups are generally those who have problems with the digesting dietary fats or anyone who is prone to hypoglycemia. Obviously, the best way to deal with a ketogenic diet is to consult your doctor first and ask if there are any contraindications: conditions or problems that might put you at risk when on this diet.

However, the percentage of the population that is likely to experience negative health effects on a keto diet is very small.

12. How much weight can I lose?

This depends entirely on how much you’re eating and how many calories you’re burning.

The keto diet won’t give you a specific, predictable amount of weight loss all by itself. It will help you maintain an effective deficit and burn fat efficiently, but it won’t make huge changes to how your body works: you still need to eat less than you use. As you do this, you’ll lose weight.

13. What foods can I eat?

You can eat most foods, though you’ll want to focus on high-quality foods and maintaining a balance in your diet.

There are some typical foods you’ll get familiar with on a ketogenic diet: fatty fish, poultry, lean red meats, plant foods, fibrous fruit, various plant-based oils, and carb sources that provide your minimum requirements in a form that isn’t highly-processed or sugary. These are the staples of a ketogenic diet.

You’ll also need plenty of nuts and seeds. These are crucial to make up for the absence of whole grains and pulses, which are very important nutrient-sources in a mixed diet. Deficiencies of magnesium and other minerals can be a real concern for a ketogenic diet, but nuts and seeds are an amazing source of high-quality dietary fats and key nutrients.

14. Will keto cause constipation?

Only if you do it wrong.

Constipation on a ketogenic diet isn’t uncommon, but it should be. The problem here is usually a high quantity of saturated fats mixed with a low quantity of fibrous foods. This is one of the reasons why we consider it important to watch the balance of your meals more closely on a ketogenic diet.

If you’re eating a meal that is all coconut oil and lean meats, you’ll run into the problem of constipation. However, if you add in a healthy serving of 1-3 fibrous, high-quality plant foods, then you’ll start to mitigate the problem. Fiber is so your friend, people. Learn to love the stuff. Your digestive system absolutely will.

The keto diet requires you to take your eating more seriously, and this doesn’t just mean cutting carbs: it means fixing your approach to the way you eat. Make sure you’re eating fibrous fruits and vegetables with every meal.

15. Will keto cause diarrhea?

As with constipation, this is only a problem if you’re doing the ketogenic diet incorrectly.

Diarrhea on a ketogenic diet is the result of consuming too many oily foods without sufficient bulk in the same meal. As with the constipation issue, it can usually fixed with a proper balance of fats to fiber, as well as ensuring that you’re getting your daily 30g of carbs from healthy, high-quality plant sources.

There can also be concerns with some of the food combinations you might run into on keto. For example, if you have a cup of coffee in the morning, followed by sugar-free Greek yogurt and blueberries, and then fatty fish for lunch, you’ll likely experience some digestive “looseness”.

The foods themselves are fine, and your overall diet may be just fine, but the short-term implications of your food choices matter to your digestive system, as well as the total of what you eat in a day.

16. Can I drink alcohol on keto?

Fortunately, no.

To start with, drinking alcohol while on any diet is a bad idea. Not only will you see worse effects from the mild toxicity that alcohol brings, since you’re underfed and have increased absorption, but alcohol is a form of sugar.

Alcoholic drinks are pretty calorie-dense (at 7 calories per gram), and they’ll do two key things that we want to avoid:

• Knock you out of ketosis
• Suppress the crucial anabolic hormones that help you build/maintain muscle and reduce/burn fat

There’s no reason to drink on a diet – especially a ketogenic one.  Sorry, folks.

17. Can I build muscle on keto?

Kind of.

The ketogenic diet is absolutely not designed for large muscle gains. It is a diet that aims to improve endurance performance, and it comes with a few key problems that will face anyone that wants to build serious muscle.

First, protein limitations will hamstring muscle growth. This is obvious from the fact that it is an “adequate-protein diet.” Adequate and optimal are very different in this regard, and a muscle-building diet will only be maximally effective if you provide your body with the raw materials for effective recovery and growth in the muscles and tendons.

Second, keto directly interferes with the muscle-building process. Building muscle happens through a few processes – the most important of which is called “mTOR”.

The problem is that the compounds that your body uses for this process are negatively affected by the ketogenic diet. This has been seen as a serious inhibition – with rodent studies showing around 55% reduction in muscular growth while on a ketogenic diet.

Obviously, these aren’t human studies, so the degree of difference can’t be taken to be straight across, but it is a clear signal that keto is a weight-loss diet!

Finally, ketosis relies (at least partially) on a caloric deficit. This should be obvious: effective metabolization of body fat stores only really works when you’re pushing your body to use body fat in the first place.

If you’re eating a diet that provides ample calories to meet your needs, your body will not rely on stored energy to meet the shortfall. This means that a ketogenic diet – with a calorie surplus – is slightly pointless. You’ll convert fats and proteins to glycogen for use in the body and either negate your keto-adaptation or simply drop out of ketosis entirely.

One final time: the ketogenic diet is a weight-loss diet!

18. Should I take supplements while on keto? Which ones?

Supplementation should be exactly that: a supplement, or addition, to a good diet.

This means that the supplements you should take on keto are effectively the same as those on a regular mixed diet. There are a few that you might want to take to ensure you’re avoiding common deficiencies (such as magnesium and electrolytes), but you can fix those with your diet too, if you’d rather not.

There are only a few essential supplements for keto. Cod liver oil is the first, especially if you’re not eating much fatty fish. The keto diet may be one of the few diets (alongside Nordic- and Japanese-style diets) that can provide enough omega-3 fats from food alone, but it’s not worth chancing it. Cod liver oil provides plentiful amounts of these brain- and heart-protecting fats.

Vitamin D is also crucial – for everyone. As you won’t be drinking a lot of milk, supplementation is the only way to get it other than through near-constant sun exposure, which carries a huge risk of skin damage and even cancer.

19. I feel bad after starting keto – what is happening?

This is often referred to as keto flu, but in reality it’s just a combination of dehydration, lowered carb stores, and a loss of dietary electrolytes. You can usually get past this within the first week of a keto diet by simply being diligent with hydration, adding sea salt to foods, and keeping your plant food intake high.

This should reduce any concerns you might have about nutrient deficiencies or other common problems. These are also just useful rules to follow for your diet: improving hydration and getting optimal levels of vitamins and minerals are what make this diet healthy.

20. What foods should I avoid?

There are really only two groups of foods you need to avoid.

The first is obviously high-carb foods. These would defeat the very point of a ketogenic diet – specifically those that are high in sugar or low in nutrients. These foods will provide far too many carbs with very little nutritional value. A single serving is likely more than your daily carb allowance.

The second group is low-quality fats. This doesn’t just mean saturated fats, however. It means fats from poor-quality sources like butter, bacon and other foods that either have a poor balance of fats

Excess intake of carbs is a problem that the ketogenic diet aims to fix – but don’t replace it with blind consumption of any and all fat. Quality comes first, and an effective diet is about setting a higher standard for your eating, whether that is carbs, fats, or proteins.  

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"My name is Jen Beall and I am 34 years old and I have an autoimmune disorder (sjogren's syndrome).  I've been on Keto for about a year now and it has changed my life tremendously especially having a disorder.  I don't feel sick anymore and have way more energy than before.  So far I have lost 50 lbs being on Keto and working out 4-5 days a week.  It really has changed my life!" - Jen Beall