The FastDay Forum

I've been on the IF lifestyle (I don't like to think of it as 'dieting' because that suggests I'm going to give it up at some point) for around 6 weeks and the only negative thing has been feeling the cold more than usual. Everything else - feeling fitter, losing weight, my knees are better (probably because they have to carry less around) my digestion is 100% better and I feel liberated from food! I believe in a few years the NHS will be advising people to have a couple of low calorie days a week and to consider skipping meals - under supervision of their doctor of course! Why are we all so afraid of hunger when diabetes and heart disease are so much more terrifying?

Questions I have which aren't answered in the FAQ board:
I know someone of 80 who has started the 5:2 because of weight and other health issues - is there any particular concern about someone of this age who knows how to eat properly going without food?

My daughter of 15 wants to fast because of weight concerns - why is the advice for children never to fast (when muslim adolescents do so regularly)? What advice does anyone have about this? After all we are meant to encourage our children to get into good habits.

Why are we always told that the first loss of weight in a diet is always fluid? Why don't we feel dehydrated if this is the case, where does the fluid come from?

Why would people's breath be bad on the basis of missing a couple of meals?

I'd be really grateful if anyone has any answers to the first two questions, the second two are really just an indication of my scepticism but if there is a scientific answer to them it would be interesting to know!

[Moogie]

Hi & welcome Anita!

We have members here in their mid to late 70's, some of whom have been fasting for a longer period than most of us! I'm sure as long as your friend is aware of what they are eating and how they feel when fasting it will be just fine - although personally I would suggest a GP consultation just to be sure if there are any underlying health issues.

5:2 is not recommended for children as they are still growing and therefore depleting IGF-1 could be detrimental. I would not suggest she considers this lifestyle until she is an adult.

The fluid question I believe has something to do with water being bound to fat, and being released as the fat bursts? I'm not 100% on this and I'm sure Caroline or someone will come and give you a helpful response on this one!

Likewise I'm not sciency enough to full understand the bad breath thing but I recall it being something to do with ketosis.

Short term fasting leads to depletion of the carb reserves held as glycogen in the liver (and muscles). Each gram of glycogen is stored with 3-4g of water which are released when the glycogen is "burned" hence you tend to pee more and lose water weight.

Reduced carbohydrate intake also reduces sodium and water retention by the kidneys, so again you lose more water.

Ketones are produced when fat is being used to fuel the body more than usual, if the levels in blood rise sufficiently there is some loss into breath and urine which can smell a bit "fruity".

Thank you for your very quick and helpful responses!

[carorees]

I an aware of two potential issues for fasting in older age. A reduction in IGF1 levels in elderly people is associated with frailty. Too much fasting or low carb diet can affect the heart muscle. So for your 80 yr old I would suggest a bit of caution. Clearly losing weight is the most important thing for improving health, but if they have heart problems, perhaps shorter fasts with a greater calorie allowance (could be done more frequently if no weight loss) would be better. Really the persons doctor should advise them.

Regarding fasting for children, we have a paediatrician who posts occasionally. He is interested in the idea of fasting to treat childhood obesity, so clearly it is not out of the question. Perhaps you could post your question in the thread he is running? viewtopic.php?f=10&t=765&p=5094#p5094

Thank you - that's helpful.