I’m eleven days in to a six week attempt at the 800 calories a day diet. I am very active, walking on average at least five miles a day and I am riding my horse some days and mucking out stables for an hour a day which is quite heavy work. I am 5’3” and weigh 10.9 ( I started at 11.9!) does anyone think I should maybe up my calories to 1000? I am suffering from weakness and I’m very lightheaded .

If you have adapted to fat burning then your energy levels should be fine with no light headedness, even on 800 calories, and even if you are exceptionally active. People have run 10k on 800 days and I regularly do two hours of badminton practice/social games in a day which is quite a lot of activity, maybe almost as much as my intake when the rest of the days activity is taken into consideration as well. This may be a drawn out version of carb flu, in which case, although you shouldn’t up your carbs, no harm will be done to the process by upping your calories, and in fact if you up the healthy fats it may help the adaptation. Try a couple of days at 1000, higher fat or protein but low carb, and keep going. Hopefully it will settle down in the next few days.

Hi Kat…

I started the fast 800 about 11 weeks ago and have had some amazing results. post here: https://thebloodsugardiet.com/forums/topic/new-t2-tacking-my-bsd-fast-800-journey/

I too had similar concerns as I typically burn between 2500-3500kcal a day, so 800kcal was a huge deficit. I keep strict track of calorific intake via my Fitbit. Looking back at my records I would say most days I was at around 900cal with even the occasional 1000kcal. I lost 15kg (33lbs) by the end of week 8 and I am in a healthy BMI range (24). I also felt very lethargic and lacking energy for the first two weeks and carb flu hit hard. I struggled to exercise at normal intensity levels, which to be fair I expected to be the case. However my body did soon adapt. I don’t think upping calorie intake just a little will do any harm for somebody active like yourself. I suspect you would still get greater losses and find it as tough (or tougher) than somebody less active on 800kcal.

Good luck with your efforts. I know everyone says this, it really does get easier the further along you get. 👍

Hi Katon….. when I started on the diet I had to reduce my exercise to manage my energy levels. It is the food intake that causes weight loss with exercise adding very little value weight wise although good for overall health and fitness. Eleven days in you should be starting to get used to the reduction in calories or, as I did, time your exercise to coincide with having had something to eat so you are not exercising on an empty stomach. I see you are doing a triathlon in a few months and good luck to you. If the 800 is causing you problems then increase a little as Jimmy says, just dont give up on the diet as you can have both with small adjustments to both exercise, timing and calorie intake. Something I say and get pilloried for is – if you are not diabetic or doing it for serious health problems, then dont sweat it, just do the best you can, try to stick to the low carb principles and make it something you are able to stick with. Good luck with the triathlon – rather you than me but I am nearly 65.