Monday, 23 July 2007

A (retired) chemist's view of diets.

The sedentary life has not been kind to me; too little exercise and too much temptation. So the need to reverse the trend has been faced and things are moving along in the right direction.

A few thoughts on dieting from a chemist's perspective:

1. To a chemist a diet is a simple issue of a mass or energy balance. Your body needs a certain amount of food per day. If you eat more than that, the excess will be stored as fat. If you eat less than that, fat (or protein) reserves will be drawn on to make up the difference.

That's it really.

You can mess around with low carbohydrates, proteins and fruits, grapefruit or whatever but you cannot avoid the simple truth of an energy balance.

If you eat more than you need, you store the balance.

2. Some people say that they cannot lose weight. They have low metabolism. Really? If I locked them in a room with nothing but water would they waste away and die? Yes, of course they would. Therefore there must be a point, somewhere between zero and present intake that is the right amount for them.

No fat people came out of Auschwitz.

3. The local chemist had a sign up "Lose 10kg in a month". Tricky. For a male, the recommended daily maintenance diet is 10,600kJ (2,535Cal). One gram of fat is equivalent to 37kJ. Therefore 10,600kJ is equivalent to 286g of fat. So if you fasted for a 31 day month you could expect to lose 8.9kg of fat. But no-one is going to fast for that long. So the whole thing is a sham.

4. I remember once being told that hard-boiled eggs were best diet food because your use more energy to metabolise them than they actually contain. Also tricky. This means that if I locked you in a room with nothing but water and hard boiled eggs you would starve to death.

I don't think so.


  1. The 10 kg in a month could be true, but a fair percentage would be water weight.

  2. What if you locked me in a room with nothing but water and chocolate chip muffins?

  3. Just don't lock me in a room! I'd lose weight climbing the walls but there must be an easier way.

    Dave - that made me laugh out loud. For a long time.

  4. Dammit! I just took my first mouthful of spaghetti bolognese! I guess I'll have to wait until next month!

  5. lee, the best weight loss program i've found is falling in love... i once lost 20 pounds without even batting an eye... well, i exaggerated a little... true, my eye did not bat, but i swam and ran and rollerbladed and did sit ups and stopped drinking wine for a while just to try to outrun the forbiddeness of my infatuation. 20 pounds dropped off like magic. good luck to you succeeding in whichever program you commit to. big hugs, snow

  6. are the Alaskan tales of rabbit starvation untrue? I've been told that the meat is so lean you can starve on it in winter because your energy needs are so high in the Alaskan cold.

    If it's true, then you could lock the subject in an ALASKAN closet in winter with water and rabbit meat and they'd lose... location, location, location!

  7. Mr. Kennedy,

    What IS this preoccupation with locking people in rooms?

  8. Logic, Lee, if only it could influence our behaviour as much as emotion does.

  9. Yes, it all goes in through the mouth.
    Water and hard boiled eggs, eh? The constipation would have to be factored into the weight gain.

  10. "No fat people came out of Auschwitz."

    I can't WAIT to use that line on someone. Of course, it would probably be considered to be so unpolitically correct here (in the US) that I'll most likely get lynched for saying such a thing.

  11. I don't want to think so much about the kind of foods or diets..too complicated. I prefer to just make sure I move my body..that's easier.

  12. Locked in a room with hard-boiled eggs... Hmm, you might not starve but you'd certainly have some other problems.

  13. I have noticed that those who have been starved (concentration camps, prisoners on the Japanese "Railway of Death", etc.) often go on to live to healthy, hardy old ages.
    What does the chemist say about that, Lee?

  14. Good question. I don't know enough about the biology of it all but it is certainly well documented that people on reduced calorie intake live longer.


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