Welcome to The Fast Diet › The official Fast forums › Body › General health › Very tired on FDs
This topic contains 5 replies, has 5 voices, and was last updated by Minka 5 months ago.
Viewing 6 posts - 1 through 6 (of 6 total)
23 Sep 17
Fell so much better since starting the FD a few months back and I have lost about 10 pounds. The only downside is I feel very, very tired on FDs – is this normal? I don’t feel hungry and drink about 4 litres of water on an FD is there something I can do to help? I eat 500 calories and include protein – any ideas?
Hi Floridajane. I find this unusual. If the amount of protein on a fast day is sufficient to fuel your body then feelings of tiredness may be a symptom of some other deficiency in your calorie intake. I am a 69 yr old male and have fasted on and off for over 4 yrs the most recent fasts being a total water only fast for aprox 54 hrs to prepare for some minor exploratory surgery. At no time did I feel tired or lethargic. Similarly during previous 600 cal fast days I have worked out in the gym with no negative effects. Can I suggest you keep a diary of your food intake on a daily basis for a couple of weeks at least. Include all days, not just Fast days. On non fast days you must eat to your TDEE and not stint on eating any less. It may indicate an area that shows a change of diet may be needed prior to or on your fast day. We are all different and what suits one person may not suit another. I am not a medically trained person and very few posters are. If all things are equal then over time it may be that you have to experiment with your diet days, both fasting and non fasting to come up with a reason for your tiredness. Sorry I cannot be more helpful.
@Floridajane. Not unusual to feel tired. It really depends on what you eat. I would hazard to guess you are a glucose burner and very poorly adapted to burning fats. When running a caloric deficit you are left with two options, burn fat to make up the deficit or reduce your expenditure. So you either feel cold or lethargic if you can not burn fat efficiently. Can I suggest that you look at your diet very closely. Get rid of sugar and processed grain based carbs. No bread, cakes, pasta, pizza etc. If its a processed grain its a no go. Get your carbs from veggies. Try and up your fat intake during non FD. Eat more cheese, high fat yogurt, avocados nuts like pecans or brazil nuts. Try and get your body used to burning fat as a fuel. Still be mindful of the overall calorie intake but incorporate more good fats.
24 Sep 17
Hi FloridaJane, I bet someone will come along who struggles with this too. I struggle more with irritation and lack of concentration on my fast days, so not quite the same, but I often spend the afternoon on the couch watching TV and telling myself I can make it to the end of the day.
The only thing I can suggest (if you can’t just go to bed and nap) is to experiment with when and what you eat. ie you might need small snacks through the day, or have your 500 early in the day, or you might even find you have more energy if you don’t eat anything.
And if it ends up that you need more food on fast days, don’t despair, Dr Mosley has found that 5:2 will still work on 800 calories on fast days.
PS You didn’t mention caffeine, is you are missing your usual pot of coffee on fast days, the lack of caffeine will turn you into a zombie!
Hi Folks – many thansk for the feedback all very useful.
Interesting about not eating at all or eating all in one go – I currently have a boiled egg in the morning, chicken salad bulked up with lettuce, home made coleslaw and sweet potato for lunch and dinner is cod with a little whole grain rice and lots of veg so I think I am getting the protein but will think about how and when I eat.
Like you Cinque I end up asleep in the chair and am a zombie from about 5 o’clock onwards!!!! Seriously thinking about the 800 low day but will see!
Thanks everyone FJ
I have a history of thyroid (Hashimotos) and adrenal issues (low cortisol) and I can feel tired and lethargic on FDs. In fact I’m experiencing one of those today! I can relate to how you feel.
Up until recently, because if my pre-existing adrenal and thyroid issues, I was careful about when I would fast to be sure I didn’t expend too much energy on a FD. Now I have little choice in this since I work sporadic days and sometimes hours and can get called into work on a moment’s notice and my work can involve a lot of physical exertion.
So, today after work, I let myself flop on the couch and nap as long as I stick to my FD plan, which I’m doing. I support you in resting if that’s what your body wants to do on a FD.
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