Food maths

[mudskipper]

I take these things with a pinch of salt.

Mmmm, pork crackling.

[NickFitz]

Sainsbury's lard is "only" 891 calories.

Surely that isn't enough? Best to be on the safe side and fry it in dripping first.

[mudskipper]

So next question: (you'll need something to wash the lard down with)

If drinking chilled water burns calories while your body warms it up, does drinking hot water make you fat?

[ctdctd]

So next question: (you'll need something to wash the lard down with)

If drinking chilled water burns calories while your body warms it up, does drinking hot water make you fat?

No, 'cos your body burns calories cooling it down?

[mudskipper]

No, 'cos your body burns calories cooling it down.

But calorie = unit of heat. Hence you lose heat/calories warming the cold water. The logical reverse is that you gain calories cooling hot water.

[ctdctd]

But calorie = unit of heat. Hence you lose heat/calories warming the cold water. The logical reverse is that you gain calories cooling hot water.

So by that reasoning, the longer you sit by the fire, the fatter you get?

[mudskipper]

So by that reasoning, the longer you sit by the fire, the fatter you get?

Sounds logical to me.

You're certainly going to get fatter sitting by the fire, than doing 100 laps in an icy swimming pool.

[EternalOptimist]

One reason why half a pound of lard will make you gain a pound in weight is skin growth.
If you get fatter, you need more skin to hold it in. The extra skin needs more blood supply, little hairs and tattoos etc.

In biology, it's known as the 'multiplier effect', where 1/2lb of lard = 1/2 * m

[ctdctd]

Sounds logical to me.

You're certainly going to get fatter sitting by the fire, than doing 100 laps in an icy swimming pool.

^ Or less thinner maybe.

So a glass of hot water means you are burning fewer calories than if you had a glass of cold water.

1 calorie is the energy required to raise one kilogram by one degree.
So, drink one litre of water at 87 degrees and I guess you will need 50 fewer calories that day to maintain your weight.

So 40-50 litres of hot water a day to maintain weight plus a vitamin pill?

Have we invented the water diet? Plan B anyone??

[Gentile]

We've all heard of foods which supposedly have a negative calorie impact - i.e. use more calories to digest than they give you.

But the opposite is true too.

To put on a pound of weight, you need to consume 3500 extra calories.

1lb of lard has 4091 calories, therefore, presumably, would cause you to put on a pound and a bit.

How can a food weigh more after digestion than before?

I'd always assumed what you weigh = what goes in - what comes out.

Food maths is certainly a weird subject. I don't think that anybody really fully understands it, or that the same intake even affects all people equally. It's hard to believe that most of the carbon that makes up a huge tree literally comes out of the carbon dioxide that it processes from thin air using sunlight. However, that's certainly what happens, despite the fact that most people would be inclined to believe that the vast majority of a tree's bulk must come from the water, minerals and other nutrients that it gets from the more tangible ground.

Similarly, for people, eating 'one calorie' of fat has a different biological effect to eating 'one calorie' of roughage or protein. And simply eating "healthily" isn't enough if a person's goal is to actually lose weight. When you're trying to do that, by definition you need to consume less energy than you're using. So, a mildly overweight person will probably stay that weight even if they eat "sensibly", and will lose weight only if they "under-eat". For someone that's already their right weight or underweight, that exact same diet would be unhealthy and a warning sign for possible anorexia.

FWIW, I tend not to worry about weight too much, since I'm lucky because I'm tall and it doesn't therefore seem to make much of a difference where I sit in a band that's about two stones from lightest to heaviest. On the occasions that I have made the odd post-Christmas effort to drop a stone or so, though, I've found two things that work for me. One, obviously, is simply under-eating as I mentioned above, and cutting out all the unhealthy stuff like fat and chocolate. It does work and you can lose a stone in about 6 weeks without straining yourself too much by that method. But, tbh, it's boring as hell and makes you feel miserable.

Another approach that I found far more enjoyable was something called "intermittent fasting". That's where you don't cut out treats like chocolate, fast food, etc, but you only eat a normal 'daily' amount every second day. It is hard for about the first 4 days, then it's a doddle as your body gets used to its new routine. (NB: You can also fast every third day, and weirdly enough that's even more effective, but is also harder since it works by deliberately disrupting your routine, making the day that you do fast feel harder since your body is still trying to use as much energy as is available on non-fasting days during that day.)

Weirdly, studies have shown that animals live longer and healthier lives when they use intermittent fasting all the time, and some people have reported the same effects. So, although it's a good method to lose weight, it's also a perfectly healthy way to live all the time; the trade off is that you live a slower, less productive, but longer life. I'm not sure I'd want to do it all the time personally. Particularly when I'm working on a difficult technical problem, I've found that I need more energy some days than others, so I can't always work it into my normal routine. For six weeks or so, though, intermittent fasting is doable, and I've found it to be just as effective for losing weight as merely eating smaller portions more often is.