The FastDay Forum

It's hub's first 'fast' day and we've planned it so that he has one weetabix for breakfast, instead of his usual two and toast.
He's just 'phoned me to say he was feeling 'very odd and light headed.' He has a Special K bar in with his lunch (salad) so I advised him to eat that.

Is feeling light headed 'normal'? What else can I advise? He also has 2 clementines (we don't expect him to hit 600 cals the first few times anyway) so perhaps one of those would help.

I don't want him to become discouraged and give up.

I've been feeling light headed too. I try to keep hydrated throughout the day, sipping water all the time, I think this helps. I am also careful not to stand up suddenly (can cause blood pressure to drop). Maybe 1 weetabix is not enough for him at the start of the day? I'd maybe suggest a larger breakfast (or something filling like scrambled eggs?). Hope he goes on OK

Does he live entirely on carbohydrates ? Beware of low blood pressure from low sodium intake, "hydration" is not about constant drinking but is about have the right fluid : electrolyte balance. A cop of bovril or the like would help if someone is short of sodium and consequently getting low blood pressure or "postural hypotension" ie low blood pressure on movement.

I too have experienced this light-headedness and slight dizziness during fast days, but much less in recent weeks or maybe I have got used to it. The advice about hydration above is good I'm sure. But fasting for a day is going to feel a little strange, and he hasn't got to the hunger pangs yet! He will need a bit of commitment to it for the first 2-4 weeks, after which it gets easier.

He's given in to a Twirl!
Thanks for all your input.

[carorees]

Hi PennyForThem

There are two possible causes of lightheadedness: low blood sugar and low blood pressure.

I think that for the first one or two fasts, the body is so unused to using fat as a fuel this results in lightheadedness when blood sugar drops once the glycogen stores start to be used up. Having a carbohydrate based breakfast and snacks makes this worse as the body again refuses to use fat as a fuel. The sooner you can get the body using fat rather than glucose for fuel the better the fasts will go. During the overnight fast before your fasting day the body is most likely already starting to use fat so to have weetabix as breakfast is a bad move. An egg or some other protein source (not milk because it contains the sugar lactose) is a better breakfast. The special K bar and the clementines are also bad news because they are high in carbs. It would be much better to have cheese or some other protein with the lunch. And again for dinner keep off the carbs if you can...have lots of veggies and some protein like fish or chicken but no rice, potatoes or pasta. That way the body is forced to use fat as a fuel. Next time, the switch to fat burning will happen more smoothly and it will continue to improve.

Fasting does cause a drop in blood pressure so if his bp is normally on the low side (whether naturally or due to meds), it could be this that is causing the lightheadedness (do you know what your OH's normal blood pressure is?). If so, then as Phil says, a salty drink and good hydration will help. Good hydration also helps with fat burning and so speeds weight loss, so there are several good reasons to keep drinking during the fast.

Perhaps he could try this for the next fast?

Thanks Caroline, can you just help me understand about the protein bit. If you eat protein (eggs, say), why does your body need to burn fat, why doesn't it just use the protein?

[carorees]

dominic

When you fast, you get increases in growth hormone production. GH is a protein sparing hormone that forces the body to use fat for energy rather than convert protein. There is a very small protein loss, but this is massively reduced due to the GH secretion.

Thanks, so what happens to the protein that one has eaten (e.g. an egg for breakfast to start a fast day)? Is it just passed through the alimentary system?

protein is firstly used for repairing things - protein is used as protein - only surplus protein is used for fuel.

So a low carb eater will be fuelled by fat, protein will do its thing and some glucose will be manufactured by the liver to provide that necessary for some organs with ketones from fat doing much of the rest (including most of the brain fuel, the biggest energy user).

ok thanks Phil, so if we run out of protein the repair team downs tools?! But most of us eat too much protein, yes? Apart from the fact that it becomes surplus fuel (equivalent to carbs I suppose) is it bad in any other way?

[carorees]

The concept of autophagy, in which the body breaks down old damaged cells to use them for spare parts is part of the repair process; too much protein interferes with this. I thought one of the aims of fasting was to promote autophagy, so I'm not certain that we need to worry at all about protein intake on fast days apart from its use in satiety.

ok thanks Phil, so if we run out of protein the repair team downs tools?! But most of us eat too much protein, yes? Apart from the fact that it becomes surplus fuel (equivalent to carbs I suppose) is it bad in any other way?

Excess protein is in part converted to glucose, so it impairs ketosis and use of fat from reserves.

The repair team run out of cement and bricks rather than downing tools

[carorees]

Didn't someone say they found that eating too much protein on fast days impaired their weight loss? Must be due to the conversion to glucose.

Now where did I read that? I was off the forum for a lot of the day and catching up with the new posts is leaving me in a bit of a muddle!