The Ketogenic Diet

So it was Resolution time last month, and you made a resolution to get into the best shape of your life. You did your research and stumbled upon something called the Ketogenic Diet. From what you have read, this might be the quickest way of losing fat and getting shredded. But is it? Read on to find out!

What is it?

The keto diet (short for ketogenic diet) is a high fat, medium protein and low carb diet. Under normal dietary conditions, our body runs on a combination of carbohydrates, proteins and fats. In a ketogenic diet, however, with a lowered carbohydrate intake, our body shifts to fats for producing energy.

How does it work – the science behind it

In a keto diet, the body basically starts using ketone bodies as a source of energy. Here are the basics that you can read up to understand the process of ketosis and ketone utilization:

What are Ketones?

Ketones, namely Acetoacetate, Beta-Hydroxybutyrate and Acetone, are produced from the condensation of Acetyl-CoA, which is a by-product of the incomplete breakdown of FFA (free fatty acids) in the liver.

When does the body enter ‘Ketosis’ and start using ketones for energy production?

When carbohydrates are removed from the diet, the body runs through the glycogen stores present in the liver and muscles to provide fuel for the body. When the body glycogen gets depleted, it results in an increase in FFA release from fat cells, and increased FFA burning in the liver. This is what ultimately leads to the production of ketone bodies and the metabolic state of ketosis.

What happens after your body enters ‘Ketosis’?


Since the body is now using ketones for energy production, glucose production and utilization goes down. Hence, the rate of protein utilization via gluconeogenesis goes down as well, something that is referred to as ‘protein sparing’This is the reason why the keto diet is called a ‘muscle- sparing’ diet. If a person is really obese, the blood triglyceride and cholesterol levels may shoot up dramatically during the first few days because breakdown of body fat can cause a release of cholesterol into the bloodstream. However, as the diet progresses, the cholesterol levels will go down.

Also, the acetone which is produced as a ketone body in this process is excreted through breath and urine. This is the reason why many people on this diet have a distinct odor in their breath and body odor.

How much Protein is required on a Ketogenic Diet?

With the onset of ketosis, most of the tissues in our body start using ketones to derive their energy requirements, apart from the brain, which is incapable of using ketones for fuel for the first few days. This shift in fuel utilization spares what little glucose is available to fuel the brain as the brain gradually adapts to using ketones as fuel. For the first three weeks on a ketogenic diet, as the brain is still using glucose for energy and adapting to ketones as a fuel, protein breakdown increases greatly.

To counter this, a protein intake of ~ 150 grams per day, regardless of body weight, or 0.8 grams/lb of bodyweight, whichever is higher, should be the minimum amount during the initial weeks.

Gradually, the brain starts deriving most of its energy requirements from ketones and to ensure that brain has an uninterrupted supply of ketones, most tissues will meet their energy requirements almost exclusively through FFA’s. When that happens, the protein intake may be re-adjusted to 0.8 grams/lb of bodyweight.

Types of Keto Diets

There are three different ways in which one can execute a ketogenic diet-

  1. Standard ketogenic diet (SKD) – This is the normal version of a ketogenic diet wherein a person consumes a diet low in carbohydrates, moderate in protein, and high in fat.
  2. Targeted Ketogenic diet (TKD) – In this version of the keto diet, carbs can be consumed around one’s workout session to increase performance. 25-50 grams of carbs can be consumed before and/or after training.
  3. Cyclical Ketogenic diet (CKD) – In this version of the keto diet, the standard ketogenic diet is coupled with high carbohydrate refeeding for a one- to two-day period, to maintain exercise performance and look leaner. This diet is employed by bodybuilders who are trying to get stage lean.

How to determine if the body is in Ketosis?

The metabolic state of ketosis can be further subdivided into two categories

  1. Ketonemia – Ketonemia refers to the buildup of ketone bodies in the bloodstream. It can be measured by doing blood tests which might be a good way of determining if you’ve entered ketosis or not.
  2. Ketonuria – Ketonuria refers to the excretion of ketone bodies in the urine, due to the accumulation of ketones in the kidney. The degree of ketonuria, however, can be measured by the use of Ketostix, small paper strips which react with urinary ketones and change color. Some individuals who may be keto-induced may not show urinary ketones. However, that doesn’t mean that they are not in ketosis. Ketonuria is an indirect measure of ketonemia and ketostix measurements might be inaccurate. The best bet would be to follow the diet religiously.

Is Keto the right Diet for you or not?

Right now, the Keto Diet is a much talked about name due to the remarkable results it tends to deliver. Many people throw the term around and decide to experimentally start the Keto diet without much thought put into it.

However, it is crucial to remember that Keto is not a magical diet which will help you lose weight faster, and especially when done without understanding how it works at a physiological level. Research has shown that when calories and proteins are equated, there is no difference in fat loss across diets.

However, keto might have some psychological benefits. When we start a keto diet, the initial loss of water weight due to the reduced carb intake may work as a boost for some people to better stick to the diet. Also, the high fat nature of the diet is more satiating as compared to other diets, which may keep an individual fuller for longer despite being on a calorie deficit.

However, when we are trying to build muscle, a keto diet may not be the most ideal. With reduced carbohydrate intake, lower levels of the thyroid hormone T3 are observed, which is known as Euthyroid Stress Syndrome (ESS). Due to this reason, low carbohydrate diets are not ideal for individuals looking to gain muscle tissue, as a decrease in T3 negatively impacts MPS.

“Side effects” of a ketogenic diet

1. Keto Flu

Many individuals who start a keto diet complain of symptoms like fatigue, dizziness, nausea and low power output during workouts. This is very common on a keto diet and is described as the “keto flu”. This happens because the body is used to using carbohydrates as fuel and now because of the limited carb intake, it has to shift to using fats for fuel. It typically lasts for about 4-5 days.

Dealing with “keto flu”

Here are some quick fixes if you feel the onset of keto flu (see symptoms above) –

  1. Water intake should be optimum (around 5-6 litres) during this period to counter the symptoms of keto flu.
  2. Due to the dehydrating nature of a keto diet, the electrolytes are flushed out of our body. To correct that –
    1. Have salt in generous amounts to replenish your sodium stores.
    2. Have magnesium and potassium rich foods like spinach, avocado, fish and meat.
    3. Adding multivitamins can help.
  3. Exercise – Go to the gym, even if you don’t feel like it. Research shows that exercising might help in getting into ketosis faster. Also, it will help you keep your mind off the keto flu.
  4. Get a good night’s sleep.

2. Constipation

Apart from keto flu, constipation is another side-effect which may occur due to the lack of fibrous carbohydrates in the diet.

Dealing with Constipation: Getting enough fibres from your diet in the form of leafy non-starchy vegetables reduces the risk of constipation.



Do remember, the Ketogenic diet isn’t the only diet you can adopt to lose body fat. If you can’t do well without carbohydrates, you can still eat rice and lose weight if you keep a watch over your total calorie consumption and be sure to stay in deficit.

But if you do want to go for it, go for it. Just be consistent with your diet. In the end, it all comes down to consistency and patience. Follow the diet religiously and a trip to the tailor’s awaits shortly.

Happy Dieting!


Article Credits – Sandeepak Ghosh (Guest)



  3. The Ketogenic Diet- Lyle McDonald