Fat Chance: a guide to natural slimming aids


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From fibre and appetite suppressants to compounds that break down and burn fat, the fact is slimming pills sell. But what are the real facts behind these touted flab-busters and do they really work? Paula Bartimeus DHD, checks out the latest slimming aids

Imagine a “miracle” pill that has no side effects but dissolves excess body fat in a matter of weeks. Sounds too good to be true? Well you’re right! Unfortunately, most of us have to shed those extra pounds the hard way, by sensible eating habits and regular exercise. However, putting aside unscrupulous product claims by some unethical companies, there are a number of nutritional supplements that have been found, in conjunction with lifestyle changes, to encourage a reduction in weight loss. Below are ten natural slimming products with an explanation on how they work.




Conjugated linoleic acid (CLA) has been described as the missing link in weight management. This is due to a reduction in the consumption of CLA rich foods, such as beef and dairy produce (ironically the foods that are avoided by those trying to lose weight), and also because CLA production in the rumen of cattle is dependent upon pasture feeding which is becoming less prevalent.

The naturally occurring fatty acid was accidentally discovered over 20 years ago by Professor Mike Pariza of the University of Wisconsin, USA, when he was researching the potential cancer-forming properties of fried hamburgers. CLA was isolated and found to be anti-carcinogenic. During research into this property, its effects on body fat and fat storage were discovered. A growing body of research in the USA and Europe now shows that CLA reduces body fat and increases lean tissue. CLA appears to work by increasing the enzyme activity relating to the fatty acid beta-oxidation in the fat and skeletal muscle. These enzymes are responsible for the utilisation of fat as energy and the deposition of fat. Another possible mechanism is CLA’s ability to act as an insulin sensitiser, lowering insulin resistance and insulin levels. Raised insulin levels are believed to be a factor in obesity.

In 1997, a study showed that there was a 15 to 20% reduction in body fat in people taking CLA over a three-month period, as opposed to those taking a placebo.(1) Other studies have shown similar results.(2) In his latest research, Pariza has shown that CLA also alters the way in which weight is regained following a diet. Weight is usually regained at the ratio of 75% fat to 25% lean tissue, but people taking CLA regain weight at a 50:50 ratio with resulting benefits for body shape and well-being.(3)

Suggested supplemental intake
1000 mg three times a day after food.




Chromium is an essential trace mineral that is required for the maintenance of normal blood sugar levels. In light of this, it may help curb cravings for sugar and refined foods, thus reducing the intake of empty calories.
Chromium, in a form called chromium picolinate, has been studied for its potential role in altering body composition. Preliminary research in animals (4) and humans (5,6) suggested that chromium picolinate increases fat loss and lean muscle tissue gain. Though some follow-up research in people has not confirmed chromium picolinate to have a significant effect in altering body composition (7), research has reported a reduction in body fat(8) and body weight (9) in people given 400 µg of chromium picolinate a day for three months. The double-blind study involved 122 moderately overweight people and resulted in an average weight loss of 6.2 pounds of body fat, as compared to 3.4 pounds in the placebo group.

As chromium (like other trace elements) can be potentially toxic when taken in high doses, amounts of more than 200 µg a day should not be taken for more than three months, unless under the supervision of a healthcare professional. Chromium in doses of 50 to 200 µg a day is safe to take long term and complies with the Upper Safe Levels for supplements for long term use issued by the UK Council for Responsible Nutrition (CRN) and the European Federation of Health Product Manufacturers (EHPM).

Suggested supplemental intake
400 µg daily after food for three months. Then, 200 µg daily.




Hydroxycitric acid (HCA), a derivative of citric acid, is extracted from the rind of a small, sweet, purple fruit, namely Garcinia cambogia. Also known as the Malabar tamarind, the fruit is the richest known source of HCA and has been used extensively in South East Asia for hundreds of years.

HCA’s main mode of action is to partially block the conversion of carbohydrate into fat. It also appears to activate the enzyme carnitine acetyl transferase, which increases the rate at which fat is converted into energy.
Animal research indicates that HCA suppresses appetite and induces weight loss.(10,11,12,13) One case report found that eating one-gram of fruit containing HCA before each meal resulted in the loss of one pound a day.(14) To date, three small clinical trials have been undertaken in humans, which showed significant results. However, these trials have yet to be published. HCA is best taken in combination with other potential weight reducing compounds such as chromium.

Suggested supplemental intake
250 mg 30 minutes to one hour before main meals.




Although strictly speaking L-carnitine is not an amino acid, it does have a similar chemical structure, and is therefore often classified as one.
Carnitine was first isolated from meat in 1905; however, its role in human physiology wasn’t identified until 50 years after its discovery. It was found that carnitine is needed for the transport of fatty acids into the mitochondria of cells, where they are burnt to produce energy. Consequently, carnitine increases the metabolism of fat, while boosting energy levels as well.

In a preliminary study of overweight adolescents participating in a diet and exercise programme, those who took 1000 mg of L-carnitine a day for three months lost significantly more weight than those who took a placebo.(15)
Nutrition consultant, Alexander Luce says, “L-carnitine may be beneficial in fat loss when taken on a long term basis in combination with regular exercise.”

Suggested supplemental intake
500 to 1000 mg twice a day on an empty stomach.




Spirulina is a blue-green alga, commonly sold as an option to multivitamin and mineral products. It contains a number of nutrients, including vitamins and minerals, and other factors such as highly absorbable protein, essential fatty acids, enzymes, chlorophyll, and nucleic acids.

Spirulina may be beneficial in weight management due to the high level of phenylalanine that it possesses. Phenylalanine, an amino acid that works by suppressing the appetite, is also available in an isolated state, often recommended for this purpose. Russian scientists found that spirulina contains thyroxin factors, which may nourish the thyroid gland. As an imbalance of this gland is sometimes implicated in weight problems, spirulina’s influence on weight could also be due to the stabilising effect it has in this area.

In one double-blind study of 16 overweight individuals, ingestion of 2.8 gm of spirulina three times a day for four weeks resulted in weight loss.(16)
Besides having the potential to reduce weight, because spirulina is a rich source of many nutrients, it may help prevent nutritional deficiencies in those on a reduced calorie intake i.e. those on weight loss diets.

Suggested supplemental intake
2 to 4 gm 30 minutes before main meals.




5-hydroxytryptophan (5-HTP) can be manufactured in the body from the amino acid L-tryptophan, which is present in many dietary proteins. However, eating food that contains L-tryptophan does not significantly increase 5-HTP levels. For this, a supplement is required. Supplemental 5-HTP is naturally derived from the seeds of Griffonia simplicifolia, a West African medicinal plant.
Although the primary therapeutic use of 5HTP is as a natural antidepressant, preliminary research has shown that it may be implicated in weight loss. It is believed to work by raising serotonin (an important brain chemical) levels, which in turn affects factors such as sleep, emotional moods, pain control, inflammation and appetite.

Appetite reduction and weight loss (averaging 11 pounds in 12 weeks) has occurred with amounts of 600 to 900 mg daily. (17, 18) In another study, 750 mg a day has been shown to be effective at decreasing carbohydrate and fat intake and promoting weight loss.(19)

To avoid raising serotonin levels excessively, 5-HTP should be avoided with certain medications such antidepressants, weight-control drugs, other serotonin-modifying agents, or substances known to cause liver damage.

Suggested supplemental intake
50 to 100 mg with evening meal.




7-KETO (3-acetyl-7-oxo-dehydroepiandrosterone) is a naturally occurring breakdown product of the hormone dehydroepiandrosterone (DHEA). 7-KETO’s association with weight loss is due to its ability to raise levels of T3, a thyroid hormone that plays a major role in metabolic rate.

In one study, overweight subjects were given either 100 mg of 7-KETO twice a day or a placebo.20 After 8 weeks, those taking the supplement lost an average of 6.34 pounds, compared with 2.13 pounds in those taking the placebo. The percentage of body fat also changed – with a loss of 1.8% in the 7-KETO group, with only 0.57% in the control group.

Because the long term safety of 7-KETO has not been established, the product should not be taken for longer than two months, unless under the supervision of a healthcare professional.

Suggested supplemental intake
100 mg twice a day on an empty stomach.




Pyruvate is naturally formed in the body during the metabolism of protein and carbohydrate. In addition to food sources such as red apples, cheese and red wine, it is available as a dietary supplement.

Several studies have shown that pyruvate in amounts of 6 to 10 gm a day (combined with an exercise programme) aids weight loss and fat reduction. (21, 22, 23) This may be related to its effects on metabolic rate, which in animal studies suggests it increases. (24) Pyruvate may also function as an antioxidant. (25,26,27)

Suggested supplemental intake
2 gm three times a day on an empty stomach.




Fibre contains bulk and tends to produce a sense of fullness, which allows people to consume fewer calories. Some studies have shown that supplementation with a source of fibre enhances weight loss. (28, 29, 30) Fibre supplements, such as psyllium husks, may be beneficial in reducing appetite, which in turn may influence satiety and weight loss. Psyllium, a soluble fibre, dissolves in water to form a gel. This mixture slows stomach-emptying time, and is likely to prevent the urge to snack in between meals. Fibre supplements should always be taken with plenty of water, so that they can effectively perform their task.

Suggested supplemental intake
1 tablespoon twice a day with two glasses of water in between meals.




Udo Erasmus, author of Fats that Heal, Fats that Kill (Alive Books), states that Omega-3 essential fatty acids can be used for weight loss. He says “One woman in California lost 80 pounds of excess fat by adding three tablespoons per day of fresh flax oil to her dietary programme. She had been eating relatively nutritious foods for some time, without effect. The addition of the flax oil was the missing key for her. Weight watchers may find it hard to believe, but here is a fat that can make fats burn more rapidly.”

According to Erasmus, Omega-3 fatty acids help reduce weight in three major ways: they are precursors of series 3 prostaglandins, which encourage the removal of excess water held in the tissues; they help increase metabolic rate, oxidation rate and energy production; and because they boost energy levels, they encourage activity, which in turn burns more calories.
Suggested supplemental intake

1 to 3 tablespoons of flax seed oil a day added to salads, wholegrains and vegetables. (Due to the instability of essential fatty acids, flax seed oil should never be heated.) Flax seed oil is also available in capsules.




Slimming aids, as already mentioned, should be taken in combination with a healthy, calorie controlled, diet and supplemented with a regular exercise programme. Crash diets should be avoided and the aim should be to lose no more than one kilogram or two pounds a week. Although some weight loss compounds can be used in combination, care should be taken not to take too many at the same time. If a combination is desired then it’s wise to opt for products that have already been combined by manufacturers or choose supplements that have different functions e.g. CLA for fat reduction, chromium for blood sugar stabilisation, and fibre or HCA to reduce the appetite. After two months, if steady weight reduction is not achieved, then it may be necessary to consult a nutritional therapist, who will be able to assess possible problems such as food allergies/intolerances, thyroid dysfunction, poor digestion etc…which may be hindering the body’s ability to lose weight.




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