The Common Side Effects of Starting a Ketogenic Diet

If you want to lose weight fast without starving yourself, the Ketogenic Diet is a great choice.

Ketogenic diets are low in carbohydrate, contain moderate amounts of protein and are high in fat, result in very fast and dramatic weight loss but are also sometimes accompanied by a few, short-term, and non-serious, side effects.

Reducing your carbohydrate intake means your body has to seek out an alternative source of fuel.

That alternative is fat.

However, it cannot use fat directly and has to turn fat into a substance called ketones that is CAN use.

This process is very uneconomical and a lot of fat only makes a small amount of ketones.

This inefficiency leads to fast and easy fat loss. 

However, transitioning from using carbs for energy to using ketones can take several days and during this time, some people experience side effects.

Once your body has made the switch to using ketones exclusively, these side effects will completely disappear, but in the interim period, a few side effects are quite common.

Frequent Urination

As ketones start to build up, your body will try and rid itself of any remaining carbohydrate in your body by releasing glucose into your blood.

Excess glucose in your blood are filtered out by your kidneys and then excreted in your urine.

After a few days, your urine output will normalize and signifies that you are no longer excreting glucose in your urine.

In fact, if you test your urine using a keto stick, you should see the presence of ketones and not glucose.

This means you are now in “full fat burning” mode. 


Your body, and especially your brain, like to run on carbohydrate.

This is mainly because that’s what it has done for many years.

When you suddenly reduce your carb intake, it takes a few days for your body to switch gears to using ketones.

In this period, there are too few carbs and also too few ketones, and subsequently, some people feel tired.

Plan for this by avoiding strenuous activity during your transition and maybe even starting your ketosis during the weekend to save feeling tired at work or school.


Headaches are often triggered by low blood glucose.

When you cut carbs, your blood glucose levels inevitably drop.

This is your brain’s way of saying that it wants more carbs.

However, after a day or two, ketone levels will rise and your brain will start to use ketones in place of carbs.

At this point, the headache will go away.

You can reduce headaches by drinking plenty of water and also eating enough salt as getting into ketosis uses a lot of salt and a sodium deficiency can give you a headache.


You don’t need to starve yourself to lose weight on a ketogenic diet, but you do need to stop eating carbs, limiting your intake to no more than 20 to 50 grams per day.

This means that some people will start craving bread, rice, pasta, cereals, bread, potatoes and sugar.

These cravings will go as soon as you get into ketosis and can be alleviated with things like sugar-free gum and sugar-free jello.

Also, remember you can eat a lot of food that contains protein and fat and cravings for carbs can often be silenced by eating tasty treats like beef jerky, cold cuts, hardboiled eggs, or cheese.


Carbohydrate-rich foods such as bread, rice, pasta, and potatoes are a common source of fiber.

Dietary fiber contains no calories but is important for your digestive health.

Fiber is indigestible and passes through your digestive tract intact.

In doing so, it adds bulk to your feces and ensures the smooth transit of waste through your digestive system.

Lack of fiber will reduce the size of your stool and this could lead to constipation.

There are, however, plenty of low carb fiber options.

Greens, for example, such as lettuce, cabbage and kale, all contain lots of fiber but virtually no carbs.

You can also use fiber supplements such as psyllium husks.

Metamucil may also be helpful.

In many cases, simply drinking more water will alleviate constipation quickly and easily.


Low blood glucose levels can keep you awake.

When you initially reduce your carb intake, your body goes into “alert mode” as it mistakes low blood glucose for starvation.

This results in a heightened awareness designed to make you better at sourcing food which simply ends up interfering with sleep for a couple of nights.

Avoid caffeine in the hours before bedtime and take a relaxing warm batch to help prepare you for sleep. Y

our normal sleep patterns will resume once you have entered ketosis.


The Ketogenic Diet is a safe, fast, and effective way to lose weight.

However, getting into ketosis can be a shock to your system.

The mild and short-lived side effects indicate that your body is making the necessary changes required to turn you into a fat-burning machine and are nothing to worry about.

If you can tough it out for a few days, you will be rewarded with faster fat loss than you ever believed possible!