Weight loss part two - nutritional mathematics

A well-known story...

A person close and well-known to me confided that she is starting a diet to loose weight. Of course I asked how much she would like to loose, in what time period and how she is planning to achieve it. So, her approach is to loose 5kg in 2-3 weeks, by using SlimFast - she exchanges 2 of her 3 meals a day against a portion of SlimFast, which will each contain 300kcals. The rest of her diet is made up by eating lots of fruit and veg. So, that's a calorie intake of an estimated 800-1000 calories a day. Now, she doesn't do much sports (due to time constraints), but could possibly fit in about 30min of light exercise a day (e.g. cycling to college instead of taking the tram, walking to places etc). This is an extra estimated 250 calories burnt a day. Assuming that her daily base rate is about 2000 calories a day, including the sport that gives a total of 2250 calories expended per day. Her average food intake is an estimated 900 calories, so this is -2250 calories +900 calories = -1350 calories, i.e. a 1350 calorie deficit deficit a day. Now, 1kg of body fat is about 7,600 kcals. 5kg of bodyfat = 5x7,600 = 38,000 calories that need to be burned. 38,000 calories to be burned / 1350 calories used up per day = 28 days. So, to loose 5kg in this way, it will take her 28 days which is exactly 4 weeks. Which means that it is JUST NOT POSSIBLE for her to loose 5kg of fat in 2-3 weeks using her approach.

The obvious problem with this approach is that people have no realistic, i.e. achievable goals (see mathematical proof) for loosing weight (with this I mean fat, not just water) - rather, they want to loose it too quickly.

And, this is not the only problem, but actually a source of further problems:

Eating way too little (1000 calories is way too little for a normal person) creates a danger of malnutrition, which can make you feel constantly hungry craving for bad (=unhealthy, too fatty or too sweet) food and therefore at the brink of giving up, cold and down, and on top the metabolism tends to slow down when you eat too little which means when you start eating again as you did before the diet (or even slightly healthier), the pounds will pile on in no time. It's funny, I didn't think I would find myself repeating these well known things, but I think it helps to contrast with an easier and better and more long-lasting approach to weight-loss.

Oh - as an aside, I recently read in the Metro (arguable not the most reliable information source) that according to some Tesco survey 1 in 5 men in Ireland is on some kind of diet to loose weight. Funny thing is not that, but their reason for it: to spice up their sex life! Whereas the reasons for most women is to look better for themselves, to feel better, to be healthier...

Well, the solution to yoyo dieting and lasting weight-loss is actually easier than going on a strict weight loss diet as long as you can change one thing: your habits. I have noticed it took me about 4 weeks to reach for an apple rather than a biscuit, a banana rather than ice cream, to believe that I DON'T need a second helping of dessert after my lunch etc. But once you are used to your new and healthy way of eating, your weight will shift automatically. You will also need patience. You might only loose 200-300 grams per week, but what you loose is really gone and not just water. So don't expect your weighing scales to show you a huge drop in weight in the first few days (if it does, you are probably eating too little and are loosing water mostly). It's important to keep your goal in mind: a healthier way of living and LASTING weight-loss. You WILL feel better that way and it IS easier than a strict diet. Just those two things: change your eating habits and have patience. Your new and healthy way of eating should not feel like a restrictive way of living, but a like a healthy way of eating that you want to keep forever - so do allow yourself little treats (a little piece of chocolate, not the whole 100g bar!) from time to time. If you feel your diet is too restrictive you are more likely to give it up. Maybe it helps to change little things at a time until you've reached a healthy eating balance. A little trick that helped me in the beginning was to "consider twice", like "Do I really want another bar of chocolate?" - "Yes." - "Really really can't do without?" - "Hmm, I actually don't need it."

An update on my friend's diet progress: After a few days into the diet she felt she could not concentrate on her work and felt cold all the time, so she gave it up and now eats the same way as before, not having lost a gram. She postponed her weight loss plan to an unknown time in the future...