Consultant dietician, Annchen Weideman, gives us the lowdown on the worst diet myths and weight loss tips:

Myth 1. Drink lots of fruit juice, as long as it’s pure

This diet myths really does effect alot of people. Fruit juice is concentrated, dissolved fructose (70%) and glucose (30%) - in short, it is a big shot of sugar. The average 200ml pure juice contains approximately six fruits. The human body copes well with small amounts of fructose and glucose from eating single servings of fresh fruit, where the pulp / fibre slows down rapid absorption of these simple sugars. Juices obviously don't have the same amount of fibre. This places a burden on the body to produce insulin in an effort to cope with large amounts of quickly absorbable sugars. In short, eat your fruit, don’t drink it.

Myth 2. Fat free is the only way to diet

Health authorities have recommended "low-fat" or "fat-free" diets for almost four decades. The reasoning was that fat contains more kilojoules (38kJ per gram) than either carbohydrates or protein, containing 17kJ per gram.
It makes mathematical sense that if you eat equal quantities of these nutrients, fat will be most fattening. But this equation discounts several important facts: fat offers the highest satiety value, and severely restricting it from your diet will lead to incessant hunger, and also make it a lot more difficult to stick to any diet.

The second discounted point is the GI-lowering effect of fat with meals, and thirdly, the life-saving anti-inflammatory properties of omega-3 fats. By restricting all fats, we've probably increased our exposure to inflammatory conditions such as heart disease, abdominal obesity, hypertension, diabetes and certain cancers.

Myth 3. Base your meals on cereals and starches

The Food Guide Pyramid has indeed become our tombstone. Many years of starchy eating (6 – 11 portions per day, as recommended) have fuelled our abdominal fat stores. This could lead to an increased production of insulin in response to chronic, large amounts of blood-sugar release from starches.

Fresh fruit and vegetables are a healthier alternative to starchy eating, since their biochemistry call for a smaller insulin release. Fresh fruit and vegetables should be used to substitute half of our starches. No diet based on starch will promote or sustain weight loss.

Myth 4. Jelly babies and marshmallows are fat free, and not fattening

You are faced with the fourth diet myth every time you enter the supermarket - candies that have emblazoned, in big bold letters, "fat free". The food industry knows you confuse fats and sugars, and they exploit this. If you think you can regularly, safely indulge in a packet of "fat free" jelly babies while you're trying to lose weight, you've fallen in the trap. These products might be fat free, but contain concentrated sugar, with a high insulin-stimulating action. High insulin release is exactly what you want to avoid if you want lasting success with weight loss.

Myth 5. Eat at least five fruits daily

This recommendation assumes that these five fruits will substitute extras in your diet, such as starches or desserts. It's no use eating your daily junk diet, plus five fruits to soothe your conscience. Then even fruit is fattening.

Myth 6. Avocado is fattening

This healthy fruit has been unfairly blamed as fattening for too long. Fruit is generally fat free, and the fat in avocado is not "high fat", "bad fat" or even fattening. Also, it has no effect on your cholesterol or blood-sugar levels.

Myth 7. It's what you eat – when is not important

We often skimp on our food intake during the day, with the result that by late afternoon our need for blood-sugar replenishment overrides all reason. One of the main purposes of breakfast is to get a solid, slow supply of blood sugar going. Topped up by a sensible lunch and late-afternoon snack, your supper should be smallest of your meals.

Breakfast has 16 – 18 hours to metabolise, lunch has 10 – 12 hours, and supper usually has two or three hours before we expect our sleeping bodies to cope with the digestion of the largest meal of the day. That's why we should "breakfast like a king and supper like a pauper".

Myth 9. Breakfast cereal and muesli bars will make you thin

If you want to kick-start your insulin production to put your body in effective fat storage mode, try doing this. Having high-GI starch as your meals, plus bars loaded with sugars, harmful fats and more refined starch in between, will make sure that you become a yo-yo dieter. Be prepared to be a lot worse off than you were when you started this ridiculous diet.

Myth 10. Rice cakes and popcorn are 'free foods'

Firstly, the need for free foods means that your diet has little satiety value, or you're stimulating glucose and insulin spikes in a self-perpetuating cycle by means of bad eating habits.

Secondly, no refined starch-based foods are 'free'. The term 'free' refers to the low-kilojoule content of these foods, but by frequently eating 'free' starches, you're stimulating insulin production, and again, putting your body in good fat-storage mode. This has little to do with kilojoules.

Got some diet myths you think everyone should be aware of? Leave a comment in the section below.

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