Quick fix, faddy diets full of pseudoscience and over-inflated promises are everywhere - but these really do take the biscuit.
The tape worm diet
Put simply, you eat a beef tape worm cyst and hope that it really is a beef tape worm because if it's one that comes from a cow that has hosted a pig tapeworm you could die. Then, you sit back, eat what you like and let the tapeworm grow and grow in your innards until it dines out on your food more than you do. Unfortunately, it will compete for all your essential vitamins and minerals too so although you can expect to lose one to two pounds a week you're also likely to become nutritionally deficient. Once your target weight loss is reached, an antibiotic is given, which kills the tapeworm so it can be expelled through the er, usual means! Thankfully, it isn't possible to attempt the Tapeworm Diet in most countries, but it is still being offered in some parts of the world.
The negative calorie diet
The Negative Calorie diet works on the premise that a) some foods take more energy to digest than they have in them and b) some foods naturally increase your metabolism. Unfortunately, there are no such things as negative calories and no 'fat burning' foods. The only benefit may be in the fact that many foods that are purported as having these fat burning qualities are either fruit or vegetables which may actually have a filling effect without lots of calories.
The Israeli army diet
This is an eight day cyclical diet of apples, cheese, chicken, then salad that was particularly popular in the 1970's but still abounds today. It has no scientific basis whatsoever and was probably thought up by someone who likes apples, cheese, chicken and salad! It is as nutritionally sound as ..... well, a diet of apples, cheese, chicken and salad. However, people do temporarily lose weight on this diet because it is very low in calories. The only relationship the diet has to any army is the fact that after a few days of this type of eating you will probably wish that you could join it to get some decent nosh!
The ice cream and beer diet
(And yes, it is real ice-cream and real beer!)
This diet, mostly circulated on the internet, is based on the idea that when we eat or drink anything that is very cold the body has to heat it up to body temperature before it can be digested. This process requires energy and (as luck would have it) according to the creators of the diet the body chooses to get this energy straight from our fat stores. Therefore, the more frozen dessert you eat and the more cold beer you quaff the skinnier you will become. No points for pizza, chips or chocolate though but never mind, all you need to do is drink a lot of beer with your pizza and then poke it down with a generous helping of your favourite Haagen Daz!
How to spot a fad diet:
1. It will not be backed up by any sound scientific research and will probably only be supported by anecdotal evidence such as 'This diet helped me lose 10 stones in two weeks!'.
2. If it requires anything special to make it work such as pills or potions be suspicious. It's likely to be expensive and highly unlikely to work long term.
3. If it promises a weight loss of anything more than 2 lbs a week maximum it will be encouraging you to lose water and lean body tissue rather than fat. This means that you will slow your metabolic rate and put on more fat in the long term.
4. Make sure that it provides all the essential vitamins and minerals and bear in mind that supplementation is almost always an inadequate way of getting all the essential nutrients compared to natural eating.
5. Avoid diets that suggests an intake of less than 1200 Kcal's per day unless under strict medical supervision.
6. Reject any diet promoting a specific food, drink or potion as a fat burner.
Above all, remember that any diet that involves a temporary change in your eating habits rather than a lifelong alteration of nutritional habits will eventually result in your body returning to its original levels of body fat, if not more. The fact remains that healthy eating and plenty of exercise is still the only answer to permanent, healthy fat loss.