The ketogenic diet, or 'keto', is one of the most popular diets doing the rounds right now. Is it just a passing fad, or does it have merit as a health boosting approach to nutrition? As a qualified nutritionist who has actually used a ketogenic style diet myself, here's what I know.

Keto is a low carbohydrate, high fat style of eating. Protein is kept at a moderate amount, although some variations are higher in protein.

People following a ketogenic diet track their carbohydrate intake. The important measurement is net carbohydrates – carbohydrates minus the fibre content. Generally, a person will consume less than 50g of net carbohydrates per day. Some will often aim for 30g or less.

The aim of the game is to switch the body's primary energy system. When we consume carbohydrates, we use glucose as our major fuel source. But when carbohydrates are depleted, the body needs to create another form of energy somehow. In ketosis, the body creates a different energy source called 'ketones'.

Keto is generally an omnivorous (plant and animal-based) diet. However, a vegetarian ketogenic diet is possible. Even a vegan could follow a ketogenic diet, although it would be very restricted and could require supplements. It can also be adapted to many allergies and sensitivities, including gluten, dairy and fructose/FODMAPs.

Being in ketosis has many potential benefits. It is not just about weight loss – in fact, it has only recently become 'the' diet for weight loss. Ketosis can have effects on things such as:

That said, ketosis can also be a very effective weight-loss option, particularly for people with one of the above conditions.

Early research also suggests ketosis could be helpful for conditions such as Alzheimer's disease, Parkinson's disease, some types of cancer, PCOS and acne.

Of course, as with any diet, there are potential issues with ketosis. These may include:

It's possible that being in ketosis just doesn't suit a person's particular genetics and chemistry. I would also not recommend a strict ketogenic diet for anyone with a history of eating disorders.

There is insufficient evidence about the safety of nutritional ketosis in pregnancy and breastfeeding. So it would not be recommended to use it during these periods. 

I originally trialled a ketogenic diet over a year ago after reading research about its effects on neurotransmitters. I'd suffered from seasonal affective disorder (SAD) for years, despite trialling interventions.

Over that time I've spent about six months in strict ketosis. The benefits I experienced include:

When I am in ketosis, I am in the zone. I can work harder for longer. My energy levels are constant, my mood is calmer. I experience very few cravings and rarely feel extreme hunger.

Now, I follow a keto-style diet over the majority of winter. Over summer, I eat more carbohydrate because seasonal fruit is delicious and nutritious!

The ketogenic diet can be a good way of eating for some people. But you can also eat a very unhealthy keto diet if you're not careful! Here are my top tips for doing keto the right way.

Any major diet change is best done with a practitioner monitoring you. Seek out a keto-aware nutritionist to help you set up a plan and support you. If finances are tight, why not book in a nutrition appointment at your local Endeavour student clinic?

Just because you can't eat some veggies, doesn't mean they're off the menu. Your plate should have plenty of low-carbohydrate plant foods, including leafy greens, nuts and seeds. These give you plenty of nutrients and fibre.

A lot of people notice that they get thirsty on keto. It's not all in your mind – you actually have less fluid in your body that is supplied by the 'hydrate' part of carbohydrate. So keeping up your water intake and getting plenty of electrolytes is essential for feeling great on keto.

Just like any diet – a food isn't 'healthy' because it follows the rules. So enjoy some treat foods like desserts, but make sure most of your foods are wholefoods. Eat plenty of good fats like avocado, olive oil and coconut oil. Add in quality protein and low carbohydrate fruit and veg. But then – enjoy a square of 85% dark chocolate at the end of the day.

Keto is not a starvation diet. You should feel satiated after every meal. If you're constantly hungry and have been following keto for a month or more, you need to have your food intake assessed by a professional.

So in closing, do I believe a ketogenic diet suits everyone? Absolutely not. I'm the biggest advocate of a personalised diet. But it is a handy tool that I use for myself, and some of my clients.

It's important to understand the ketogenic diet induces nutritional ketosis, not ketoacidosis. Ketoacidosis is a rare but serious condition that can occur in diabetics, requiring immediate medical attention.

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