Lose 30 pounds or 14 kg in 30 days! Block the absorption of fat, carbs, and calories with this pill! Wear this and watch the pounds melt away. Then, and you have a picture of a hefty woman. Now, and there is the image of a slim, trim version of the same woman.

Whether you’re flipping through a magazine, scanning the aisles of a health store, or watching late-night television, you’re bound to see slogans like these touting the latest and greatest product designed to help you lose weight.

But chances are the only thing you’ll lose by purchasing the latest “miracle diet product” is money. Diet scams are a big business with sellers vying for their share of the nearly $35 billion that Americans spend each year on weight loss products and programmes.

Most of these scams could be classified as: Metabolism-boosting pills based on herbal ingredients, fat and carb-blocking pills, herbal weight loss teas, diet patches, jewellery, or other products worn on the body and body wraps or "slim suits."

Herbal formulas and medicines are not regulated by the Federal Drug Administration (US) and may not even contain what the labels say they do. The case is no different in India. Therefore, the weight loss claims are not evaluated for accuracy by the FDA or the US government. They can also have too much of a vitamin, mineral or herb, or a dangerous combination of all three that can be toxic to your system.

More often they claim to "work miracles" that are just flat out not true. In fact, a recent Federal Trade Commission (FTC) report found that more than half of the weight-loss ads that ran in 2001 made at least one false or unsubstantiated claim. “Now, more and more people seem to feel that there is some magic compound or practice, and there really isn't,” says registered dietician Althea Zanecosky. “Nobody gets the whistle blown on them unless someone dies or something really awful happens to them.”

Even when diet scams don't prove dangerous, experts say relying on pills, patches, creams and other gadgets to lose weight keeps millions of people from actually seeking weight loss programmes (like exercise) that could really help them lose weight and reduce their risk of disease.

Calorie-burning pills

Most popular diet scams are pills based on herbal ingredients that promise to boost your metabolism and help you burn calories or fat faster. The reason is simple: New herbs always seem to flash to the top as potential diet aids because in the US the FDA doesn't monitor herbs. So they don’t in India either.

The most common example is ephedra. Ephedra was found in many herbal dietary supplements for weight loss, but in February 2004, the FDA banned the sale of ephedra in any dietary supplement in the US due to the risk of illness or injury.

The herb can cause high blood pressure, irregular heartbeat, insomnia, nervousness, tremors, seizures, heart attacks, strokes, and even death. Another example is Kava. Kava is a plant found in the islands of the South Pacific. Supplements containing the herbal ingredient are often promoted for relaxation as well as weight loss. But the FDA issued a warning in 2002 that use of supplements containing Kava has been linked to severe liver injury.

Fat and carb blockers

Diet pills that claim to block your body’s absorption of fat and carbohydrates are also popular. Even if these fat and carb blockers worked as they say they do, researchers say the effects can be dangerous if not just plain unpleasant. According to Zanecosky, “It's like making someone lactose intolerant.” According to experts, by making the body unable to break down nutrients leads to gastrointestinal problems like diarrhoea, bloating and gas. These pills also block the absorption of the vitamins that travel with these nutrients.

Weight loss teas

Tea based on herbal additives are also considered as diet aids, but researchers say the main ingredient in many of these teas is caffeine, which is a diuretic and leads to water loss from the body. According to Zanecosky, “Losing water isn't losing weight.” Registered dietician Nelda Mercer agrees and says the only potential weight loss benefit of drinking herbal teas might be using them as a substitute for high-calorie beverages.

Patches & jewellery

Patches that deliver drugs through the skin have become popular for helping smokers quit and delivering estrogen to relieve stress related symptoms. But experts say no effective weight loss drugs have been designed to be delivered through the skin via patches. Most of the time, these patches contain the same ineffective herbs found in dietary supplements or teas. Also included in this diet scam category is jewellery, such as earrings or bracelets, designed to be worn on the body with the promise to help people shed pounds. According to the FTC, any claim that people can lose even a pound or more a week using these devices is totally incorrect.

Body wraps/slim suits

The thick, layered sweat suits once popular decades ago have morphed into silver "slim suits" and fat-melting body wraps designed to lock body heat in and melt away the pounds. But researchers say the only type of weight loss caused by wearing these outfits is water loss caused by excessive sweating. As soon as you take a drink, you'll gain all that water weight back.

Experts say the only way to lose weight for the long haul is to burn more calories than you eat through regular exercise and that process is slow and takes time. That means any diet products or programme that promises "quick and easy" weight loss without any effort or sacrifice is bound to be bogus

The writer is a doctoral candidate at Carnegie Mellon University, Pittsburgh, Pennsylvania, and Knowledge Editor, Financial Chronicle.