Wednesday, December 26, 2007

Detox diets : what you need to know

The indulgences of the holidays often catch up with us at this time of year. We’re feeling over-fed and bloated. So is a detox plan the way to go? Nutritionist Elizabeth Stewart gives us the lowdown on this nutritional trend.

The indulgences of the holidays often catch up with us at this time of year. We’re feeling over-fed and bloated. So is a detox plan the way to go? Nutritionist Elizabeth Stewart gives us the lowdown on this nutritional trend.


THE FESTIVE SEASON has been and gone – we have all eaten (and drunk!) well with friends and family, been on holiday, relaxed and generally enjoyed ourselves. Back to work and our usual routines and everyone seems to be talking about the need to lose weight or “tone up” after the excesses or indulgences of the past few months. Magazines have already started giving tips on how the rich and famous achieve their unachievable bodies, with diets and exercise regimes, and we become tempted to try them. After all, what harm can they do?
One that appears frequently, and in many forms, is the “detox” diet. What is it? Key in the words “detox diets” into a search engine on the Internet and up come 1,600,000 references in just 29 seconds!

The claims
What all of the websites seem to agree on is the main idea behind the detoxification diet: we need to periodically clear the ‘toxic waste’ from our bodies in order to stay healthy, because of exposure to environmental pollutants like cigarette smoke, air pollution and pesticides, and toxins from our poor diets. These toxins are said to build up in our system and the health problems they cause include weight gain, bloating, headaches, dull skin, cellulite, fatigue, aches and pains and general lack of wellbeing. A toxin is usually defined as a chemical or poison that is known to have harmful effects on the body.
The general claims made in relation to detox diets include rapid weight loss; improved digestion; improved hair, nails and skin; improved energy levels; a boosted immune system; the banishment of cellulite. Testimonials on many of the websites appear to endorse these health gains after following a detox diet.

The claims
Most detox diets recommend you go on the diet for a period of between one day and one month. Most involve fasting for short periods of time; consuming only fruit and vegetables; cutting out wheat and dairy products; consuming only a limited range of foods; avoiding caffeine and alcohol.
Although the foods allowed, and those not, vary widely amongst the different detox diets, generally fruit, vegetables, beans, nuts, seeds, herbal teas and large amounts of water are allowed. Wheat and dairy products, meat, fish, eggs, caffeine, alcohol, salt, sugar and processed foods are commonly banned.
Herbal, vitamin and mineral supplements are often recommended as an adjunct to detox diets, with the herbal supplements to help the ‘purification’ process. One of the most popular herbal supplements is milk thistle which contains a compound called silymarin, believed to enhance liver regeneration and promote its detoxification function. Clinical trials have been inconclusive; however, the extract is well tolerated by the body and the antioxidant properties may be beneficial, although not in a detox sense. Flax seeds and psyllium husks are also frequently recommended. As one of the effects of spending a period of time on a detox diet is constipation, the addition of any type of fibre into the diet is important and both of these can have a laxative effect.
Many forms of detox diet involve some type of fast, with liquids only during that time, often followed by the gradual introduction of certain foods. You are encouraged to chew your food thoroughly, drink very little while eating and relax prior to each meal.

Do we need to detox?
So is the basic premise that we need to periodically clear the toxins from our body supported by science?
The short answer is no. Our bodies constantly filter out, break down and excrete toxins and waste products. These can include alcohol, medications, products of metabolism and digestion, dead cells, chemicals from pollution and bacteria. This is done by our body’s in-built “detoxifiers” – the liver, kidneys, skin, intestines and lungs. All these toxins are excreted by the body within hours of being consumed, in the form of faeces, urine and sweat. There is no scientific evidence that a detox diet helps rid the body of toxins any faster, or that the elimination of toxins will make you a healthier, more energetic person.
In fact, a detox diet that encourages the increase in excretion of faeces and urine may cause potentially serious health problems. It can cause the depletion of essential minerals such as calcium, phosphorous, sodium and potassium which leads to dehydration and altered electrolyte levels.

What about the other claims?
Weight loss? Yes, you may well lose weight on a detox diet. Fasting or severely restricting what you eat limits the intake of energy or kilojoules, and rapid weight loss can occur, depending on the length of time the fast lasts. This weight loss is largely water and glycogen (the body’s storage form of glucose) rather than fat, which means that the weight is rapidly regained once the detox diet is completed. Lengthy fasting may in fact slow metabolic rates and the breakdown of fat stores, and result in loss of muscle. What concerns health professionals is that this rapid loss of weight, followed by equally rapid weight gain after the diet is stopped, often leads to yo-yo dieting – one failed diet followed by another. The body’s response to this is to prevent any weight loss in case it needs its stored fat and glycogen to survive a lengthy fast or lack of food.
Reduced headaches? Yes, this does happen – probably because of the elimination of caffeine and alcohol from the diet. Many people will benefit from a reduction of both caffeine and alcohol in their diets, but beware of sudden total withdrawal of both. The four or five days of violent headaches may make you head back to the coffee pot!
Less bloating? If so it’s probably because you are eating a lot less food!
Clearer skin? This can happen. It’s most likely to be from the improved hydration.
Decreased cellulite? The term “cellulite” was coined in 1973 to refer to the dimpled appearance of the skin that some people have on their hips, thighs and buttocks. This appearance is much more common in women than in men because of differences in the way fat, muscle and connective tissue are distributed in men and women’s skin. Will a detox diet decrease the cellulite? It’s doubtful, although a loss of weight (as with any diet) and therefore body fat may see the fat deposits decreased, which would mean there could be less of the dimpling effect.
Feeling better and healthier? Yes, you may feel better. But it’s debatable whether this is a result of the detox diet or a result of the loss of weight and euphoria from the perception of doing “something good” for your body. Any low fat, high fibre diet is going to be better for you than a diet high in fatty, processed food.

Are there any pros for detox diets?
Many of the detox diets on the web and in magazines do encourage good dietary habits such as eating more fruit and vegetables, drinking more water, and cutting back on caffeine, alcohol, high-sugar and high-fat foods. Any diet which encourages people to be aware of what they are eating, and to cut down on junk food and processed foods is all for the good.

And the cons…
The main problem with detox diets is that they can lead to a diet which is very short of essential nutrients. Any weight you may lose is temporary, due to loss of water and severe energy/kilojoule restriction. This can be pretty demoralising when the weight is rapidly put back on. Some people also experience side effects like feeling tired, sick and headachey. While advocates say this is the result of the body detoxifying, in reality it is caused by the lack of food. This lack of food also makes it nigh-on impossible to adhere to the diet for long periods of time.
Strict detox plans can also contribute to an unhealthy obsession with food and even the development of eating disorders.

Are there people who should never try these diets?
Yes. Detox diets are very unwise for people who are undergoing growth and development such as children and adolescents, pregnant or breastfeeding women, older adults who have impaired renal (kidney) or hepatic (liver) function, those with diabetes or heart disease, and people with irritable or functional bowel disease.

Bottom line
There is no good evidence that a detox diet is necessary or that it actually works.
The last word can be left to the British Dietetic Association:
“Detox diets are marketing myths rather than nutritional reality. They sound like a great concept and it would be fabulous if they really delivered all that they promised! Unfortunately many of the claims made by detox diet promoters are exaggerated. While they may encourage you to eat more fruit and vegetables, it’s best to enjoy a healthy, varied diet”.
Ultimately, if you still want to follow a detox diet, look for one that has the fewest restrictions and only use it to kick-start a longer term, more varied healthy eating plan.

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