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The low calorie diet (under 800 calories per day) is still one of the most popular ways to lose weight but what about halving that? What happens to the body on a 600 calorie diet? These plans often help you achieve your goal weight and do it quickly but at what expense? It�s common knowledge that cutting back on calories is necessary in order to shed pounds but an extremely low calorie diet is your metabolism�s (the sum of all the chemical and physical changes that take place within the body and enable its continued growth and functioning) worst enemy.


Muscle Mass

When you severely restrict calories your body resorts to using lean muscle mass for fuel because it�s not getting enough from your diet and no amount of exercise or protein supplement will reverse this. This might not be a problem for some people but the issue here is muscles burns energy, the more muscle mass you have the more energy (calories) are used to support them. Therefore less muscle will result in a lower basal metabolic rate or BMR (the number of calories you'd burn if you stayed in bed all day). So you may reach the weight you want quickly but at the expense of calorie burning muscle and this might be OK if you stick to diet for the rest of your life, but most of us can�t do that.

Starvation

Another problem with low calorie dieting is that it triggers your body�s starvation mode. Your body perceives a famine so it conserves energy by slowing down your metabolism. This mechanism means the body becomes super efficient at making the most of the calories it does get from food and drink. The main way it does this is to protect its fat stores and instead use lean tissue or muscle to provide it with some of the calories it needs to keep functioning. Of course, this is the perfect solution if you're in a famine situation. So once you go back to your old eating habits, which most people invariably do, the weight gained will most likely be stored as fat.

Habit

�Quick fix� diets may get results but they don�t address the real issues around weight gain and they don�t change long-established bad eating patterns and cause the body to slow down significantly. Fad diets and other short term weight loss methods are not recommended for permanent weight control.

Joanne Crovini a Naturopathic Nutritionist says, "Everyone these days wants a quick fix but that's not the way to lose weight. Weight loss and health are about eating well - having nutrient dense, whole foods and avoiding high sugar, fat and refined carb foods. We need to feed and nourish our bodies to have them functioning optimally, not deprive them."

Side Effects

VLCDs cause fat to be broken down rapidly, producing a by-product called ketone bodies. These can result in tiredness, weakness, dizziness, insomnia and nausea. Constipation, diarrhea, dry skin, hair loss, menstrual changes and a lower tolerance to cold and flu may be felt. Also according to the National Obesity Forum, there are some more serious side effects of VLCDs, including the development of gout, gallstones and cardiac disturbances. In particular, the risk of gallstones increases when people lose more than 1.5kg (3.3lb) a week.

The Big Picture

I recently asked Susan Thomason of The Food Philosophy about how VLCD tackle the long term eating habits of people who want to lose weight, "Before you choose to begin a VLCD you should phone the company and ask them for their long-term success rates � you will find that they don�t have any. This is because there aren�t any. VLCDs are not only a temporary measure but you�re very likely to end up more overweight than you were when you started. They set you up for more severe compulsive overeating problems than you had when you started and your body will be more physically damaged than when you started. The people who go on these diets tend to get into a compulsive yo-yo dieting cycle, motivated by their first fast, big weight loss (which of course is all gained back) � they keep on trying and failing and trying and failing, with shorter and shorter periods of weight loss and longer periods of weight gain until they can no longer face it and they give up. Meanwhile the damage that is done to them becomes less and less repairable."

People Respond in Different Ways

A client of mine recently completed the LighterLife 100 day 500 cal per day VCLD, I asked her about the highs and lows of her 100 days:

During the diet -"I suffered from headaches, mood swings and I felt very tired and weak for the first couple of weeks. After that I felt that my body was getting used to it, and I started walking an hour every day. I felt great and I must say my skin got better. I was drinking plenty of water and I lost 28 kgs in 100 days."

Post diet - "I did not put any weight back on and I started eating properly again immediately, not gradually adding carbs back on the diet etc - I ate everything! I strongly believe this was due to exercising, however I still have the occasional shake and soup. The fact that I lost the weight gave me the confidence to go out and exercise and I can now wear clothes that I have not been able to fit in for the last 6 years! Generally I feel more confident and happy now.

I would recommend the diet as an initial kick, but I was never interested in doing the maintenance phase of the programme, as I did not want to get addicted to the product / service. During the 100 days I benefited from the weekly drop in / weigh in and the support from the group and my coach."

"VLCDs are proven to be safe and are recognised by the National Institute for Health and Clinical Excellence (NICE) as a treatment for obesity. VLCD programmes have been available in the UK since 1984, following research that began in the 1960s. More than 20 million people in over 30 different countries around the world have now used VLCDs safely and effectively" says Jennie Saul - PR & Communications Manager, LighterLife.

It�s clear from my research; people are passionate about dieting and in the �instant gratification� society we are becoming VLCDs seem to be here to stay. There are so many reasons why we might want to lose weight and equally as many hurdles however, in my option nothing beats a healthy diet with plenty of exercise.

Like most things in life moderation is key � I�m sure we can all benefit with a healthier relationship with food no matter how we achieve it.

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