Keto diet, mood and your brain

What goes on in your brain when your diet turns 'keto'?

The keto diet has been hailed as the ultimate health kick – helping you lose weight, get fit and burn that excess body fat you have been trying to budge.

But did you know that the keto diet was developed over a hundred years ago to help with brain conditions such as epilepsy?

The amazing thing is that we may even be able to tap into these brain effects ourselves. Read on to find out how.

What is 'the keto diet’ and what does it do in our bodies?

The ‘keto diet’ actually refers to the ‘ketogenic diet’. It is a diet similar to the ‘Atkins diet’ which is low in carbohydrates but high in fat.

The fascinating thing about the keto diet is that it changes the way our body metabolises food. Metabolism refers to the breakdown of food in our bodies. Simply put, if you change what you put into your body, you change what you get out.

Our body cells ideally want to use glucose as a fuel for energy. Glucose can come in the form of carbohydrates (bread, pasta, chips…) but also includes sugars (such as the ones you add to your coffee).

If we do not give our cells glucose, it will adapt to use other fuel sources as a backup energy source, namely fat and protein.

The order your body cells will use fuel is usually in the order carbohydrate > fat > protein. This is because your body will try to preserve your important body proteins (such as muscle) - these are only broken down in real emergencies (such as in long-term starvation).

So, if we do not give our bodies glucose, it will turn to burning fat instead. The crucial thing is, when fat breaks down in our liver it produces ketones, which our bodies can use for fuel. Hence the name: the ketogenic diet.

The effects of the keto diet on the brain

Did you know that our brains use about 20% of our total body energy (who knew that thinking burns as many calories as a workout?!).

If our bodies fall short on a glucose supply, our brains will use ketones instead.

The amazing thing about ketones is that they can have nerve-relaxing effects – our cells become less excitable than when they use glucose (the reasons behind this are not yet fully understood) [1,2].

Due to the effects of the keto diet on epilepsy, some scientists are interested to see how it affects other brain disorders. Some experts have suggested that the keto diet could have mood stabilising effects [3] and could improve symptoms of depression [5] but more research is needed. Other effects include improvement of sleep disorders [4], and some even suggest it could prevent and treat diseases such as Alzheimer’s and Parkinson’s disease [4].

There isn’t enough evidence yet to say for sure. More research is necessary before experts recommend the keto diet as a treatment for any of these conditions and we do not know for sure whether the ketogenic diet benefits healthy individuals [6].

The difficulties of the keto diet

It all sounds promising, so what’s the catch?

Firstly, most people find the keto diet extremely difficult to follow. We naturally crave carbohydrate and sugars because they are the most efficient energy source for our bodies to use. You will likely find that cutting your carb intake down leads to huge cravings - and this means you could eat more sugary treats than before!

Some people even find that a drastic change in your diet can cause dizziness, headaches, weakness, nausea and tiredness [7] as your body attempts to adapt – people frequently call this ‘keto flu’! So, any dietary changes should be made slowly.

A strict ketogenic diet also involves consuming high levels of fat, which can raise bad cholesterol levels (LDL cholesterol) [7] - this is a risk factor for cardiovascular diseases such as heart disease and stroke.

Is there a better way?

It is also very important to consider that cutting carbohydrates out of your diet could lead to missing essential nutrients in your diet, which could lead to deficiencies in the long-term.

Many carbohydrates such as wholemeal bread and pasta can provide us with essential nutrients such as fibre, calcium and iron. Also, on a strict keto diet you would need to cut out many health-promoting, carbohydrate-containing vegetables – and we all know that cutting out vegetables is never a good thing.

Medical experts currently recommend a balanced diet that contains about one-third starchy carbohydrates, over one-third of fruit and vegetables and about one 10% protein, along with some healthy fats and dairy or alternatives. You can read more about a balanced diet here.

Most importantly, if you are experiencing low mood or symptoms of depression, you should always speak with your doctor, who will help you to find the right treatment and support for you.


[1] Rahul Jandial - Life Lessons from a Brain Surgeon: The New Science and Stories of the Brain [2] Lutas, A. and Yellen, G., 2013. The ketogenic diet: metabolic influences on brain excitability and epilepsy. Trends in neurosciences, 36(1), pp.32-40. [3] El-Mallakh, R.S. and Paskitti, M.E., 2001. The ketogenic diet may have mood-stabilizing properties. Medical hypotheses, 57(6), pp.724-726. [4] Rho, J.M. and Stafstrom, C.E., 2012. The ketogenic diet as a treatment paradigm for diverse neurological disorders. Frontiers in pharmacology, 3, p.59. [5] Włodarczyk, A., Cubała, W.J. and Stawicki, M., 2021. Ketogenic diet for depression: A potential dietary regimen to maintain euthymia?. Progress in Neuro-Psychopharmacology and Biological Psychiatry, p.110257. [6] Iacovides, S., Goble, D., Paterson, B. and Meiring, R.M., 2019. Three consecutive weeks of nutritional ketosis has no effect on cognitive function, sleep, and mood compared with a high-carbohydrate, low-fat diet in healthy individuals: a randomized, crossover, controlled trial. The American journal of clinical nutrition, 110(2), pp.349-357. [7] Masood, W., Annamaraju, P. and Uppaluri, K.R., 2020. Ketogenic diet. StatPearls [Internet].

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