The Health Promotion Department is concerned that many people are trying to lose weight by following the Atkins Diet, Yvette Azzopardi, principal scientific officer on nutrition, told The Times.

She said the high protein, low carbohydrate diet might lead to health risks like high blood cholesterol and heart disease because of its high fat content.

The Atkins Diet is named after its inventor Robert C. Atkins who introduced the diet in his book Dr Atkins' Diet Revolution in 1972. It is the opposite of the Mediterranean diet, which the department promotes.

According to the BBC, the theory behind it is that diets high in carbohydrates rapidly increase the body's production of insulin, which invites body cells to store fat. Therefore, by restricting carbohydrates, one avoids high insulin levels and loses weight.

In addition, the diet makes the body produce ketones, which, the BBC explains, is thought to be a sign that the body is burning its fat stores and suppressing appetite.

"The Atkins Diet is a high protein and low carbohydrate diet and this means eliminating, or drastically reducing, important food like bread, pasta and rice," Ms Azzopardi said.

She explained that the surplus of protein would also put a lot of extra pressure on the kidneys. Meanwhile, the lack of carbohydrates meant that the body did not have a quick source of energy on which it could operate.

"Carbohydrates are easily broken down into sugars and glucose that are used by the body, the brain, the organs, including the heart, and the muscles for energy. If no carbohydrates are taken in, the body would have to struggle to convert protein into energy," she said.

This could lead to a feeling of tiredness. But more serious than that is the risk of dehydration, since the kidneys would be "working overtime". Kidneys needed water to filter the nitrogen compounds that come from protein, she explained.

And since most of the foods recommended by the Atkins Diet were high in fats, especially saturated fats, this had a negative effect on the body. On the other hand, the Mediterranean diet was low in saturated fats.

Ms Azzopardi said the Mediterranean diet was based on an abundance of plant foods while animal foods, such as red meat, beef, pork and lamb, are only eaten a few times a month. Instead, one can eat poultry and fish, and legumes can be included in a meal instead of meat.

Olive oil, which contains a healthy type of fat, is used daily in small quantities and the diet also includes daily portions of dairy products. Ms Azzopardi said local milk has a lower fat content than that produced in northern Europe because of what local cows eat.

While the Mediterranean diet follows the food pyramid recommended by the Health Promotion Department, Ms Azzopardi said the Atkins Diet was the complete opposite. The protein-rich food promoted by the "fad" diet was found in the middle section of the pyramid, which meant that the body did not need it in large amounts. On the other hand, the carbohydrate-rich foods that the Atkins Diet tried to eliminate were found at the base of the pyramid, which meant that a person has the "go-ahead" to consume them.

Ms Azzopardi said many people in Malta were trying the Atkins Diet, which was highly advertised in magazines and on the internet.

"A lot of people find the conventional diet - with less fat consumed and more exercise - boring and the fact that they can lose weight in a few weeks or months attracts them," she said.

However, the nutrition expert stressed, this does not work in the long run.

"One cannot stick to such a diet for too long because it is not normal. So at one point one would revert back to previous habits and that is when they get disappointed because they gain back the weight they had lost," she said.

In fact, people often tended to gain more weight than they lost on the diet, especially if the weight loss was substantial after a few months following the diet.

"The safe way to lose weight is to do it slowly by following a healthy diet, which is well balanced with exercise," she said.

Ms Azzopardi said that in a bid to help people lose weight the department offers a weight-reduction programme. The eight-week programme is held in a support-group format with each group having an average of 15 people over the age of 25.

Applications are screened and preference is given to people who have health problems. The 350 people who took part last year lost an average of 3.5 kilogrammes each, which compares well with similar programmes in other countries.

Apart from this, the department also operates a helpline (2124-2862) for people who need help.