If you want to slam a protein shake post-workout, that's probably fine as long as you've got room for it in your macros. But shoot for one that is very low—like, zero—in carbohydrates. Pure isolates, such as Signature 100% Whey Isolate, are extremely low in carbohydrate. If you struggle to fit fat in during the day, toss a tablespoon of olive oil in with your shake. You won't taste it, and it gives a quick 13-14 grams of fat.
The good news is there are things you can do to help alleviate those symptoms. Firstly, you should see your doctor before going on the diet to get the thumbs up. Then, if you're experiencing such symptoms and they're not the result of something else (like the actual flu), start by drinking plenty of fluid, while avoiding activities that can dehydrate you such as an intense workout. Dr Evelyn Lewin also suggest increasing your salt intake by adding half a teaspoon to two teaspoons of salt into your food. if you're able to persist through these symptoms, you’ll quickly transition through this stage and come out the other side bursting with energy.
Thanks for reaching out. I don’t currently have any meal plans, but I am working on some and hope to have them up soon. I completely understand your fear, but on Keto, we don’t count calories. That’s not to say you want to start eating 5000 calories a day, but if you remember to keep your macros balanced with both fat and protein you won’t even have to worry about counting calories. I don’t ever look at calories and honestly have no idea how many calories I eat on any given day. I know when I first started my calories were pretty low but after I had got the hang of it, they went up to like 1500 a day. After about two months I didn’t watch my calories at all. The number I pay the most attention to is fat. I have to get plenty of fat, or I will stall, and I don’t feel as good. I will be sure to email you when I have my plans up so you can take a look at them.
The first modern study of fasting as a treatment for epilepsy was in France in 1911. Twenty epilepsy patients of all ages were "detoxified" by consuming a low-calorie vegetarian diet, combined with periods of fasting and purging. Two benefited enormously, but most failed to maintain compliance with the imposed restrictions. The diet improved the patients' mental capabilities, in contrast to their medication, potassium bromide, which dulled the mind.