The Atkins diet is a low-carbohydrate, high-protein, high-fat diet. It encourages the consumption of lots of protein-rich foods such as meat, fish, chicken, cheese and eggs; large amounts of high-fat foods like butter, cream, fats, oils and salad dressings but severely restricts carbohydrates such as bread, pasta, rice and fruit.

Cutting down on carbohydrates is not a new approach to weight loss. Many popular fad diets recommend reducing calories from carbohydrate as a means of losing weight quickly. However, the Atkins diet is the most well-known example of this kind of diet, mainly due to its popularity with celebrities such as Jenifer Aniston and Renee Zellweger who all claim to have lost weight on the diet.

How does it work?

The body burns carbohydrates and fat as fuel for its energy needs. Dr. Atkins believed that if a person cut down sufficiently on their intake of carbohydrate, the body would change from burning carbohydrate to burning fat as it’s primary energy source, resulting in weight loss.

The key principle of the Atkins diet is to develop ketosis by dramatically reducing the carbohydrate content of the diet. Ketosis occurs when your body does not have enough glucose for its energy needs (glucose is the primary fuel of the brain and is produced from the breakdown of carbohydrate).

When carbohydrates are limited the body must find an alternative source of energy – fat. When the body draws on fat for energy, the form of fuel produced is called ketones. Excess ketones are excreted in the urine. Conditions that favour the production of ketones are high-fat, low-carbohydrate diets and starvation.

To achieve ketosis the early stage of the diet restricts carbohydrate to no more than 20g per day. (The equivalent of one banana or a small bowl of cereal.) This is usually a period of rapid weight loss.

Once ketosis is established, small amounts of carbohydrate (about 40-60g per day) are allowed back into the diet until you reach your target weight.

When you reach your goal weight the diet allows you to gradually increase your carbohydrate intake (up to 90g) until your weight stabilizes.

Will I lose weight?

High protein diets are favoured because protein has a high satiety score. Therefore it is argued that you will not feel hungry after eating a high protein meal.

Protein also increases your total energy expenditure because the body has to work harder to release the energy from protein than from carbohydrate. However, there is a limit to which these facts are responsible for weight loss.

The real reason that weight loss occurs on this diet is due to the severe restriction on carbohydrate. When dietary carbohydrate is low, stored carbohydrate (glycogen) is used to meet the brain’s need for glucose. Diets low in carbohydrate result in low glycogen stores, which leads to fatigue and decreased concentration. Weight loss ensues but at a price.

Is it safe?

Leading scientists say it would be 'negligent' to recommend the Atkins diet. .

Research suggests that in the long-term high-protein diets may increase our risk of bone loss. In particular individuals with kidney disease, or diabetes mellitus are advised against such diets.

This is due to the fact that low-carbohydrate diets force the kidneys to handle excess waste products called ketones. A build-up of ketones in the blood (ketosis) can be risky for people with diabetes because it can speed the progression of diabetic renal disease.

The side effects that often accompany ketosis are dehydration, diarrhoea, weakness, headaches, dizziness and most noticeable is bad breath.

Over the longer term, this diet can increase the risk of atherosclerosis because of the high fat and saturated fat intakes that can be consumed on the diet. A serious criticism of the diet is that it does not include sufficient fruits and vegetables for good health and promotes the misconception that energy intake is not important.

It also makes hilarious claims such as ‘ketosis gives the dieter a metabolic advantage that allows you to sneak calories out of your body’. It may well be true that some of us have sneaked an extra mouthful of cream or tart into our mouths, but whoever heard of sneaking it out again, unused? It must be the dieters new ‘friendly thief’!!

Nothing about this plan encourages the dieter to learn about important weight management strategies such as portion control and serving sizes