What about salt Ella? I'm a very low carbohydrate eater (<100g per day) and I started getting dizzy, weak and lethargic. I learned that low carb diets cause your body to rapidly excrete sodium. The solution is obvious. I love salt so fixing it was easy for me. When I get light headed, I know I'm not getting enough. My blood pressure, by the way, is always usually around 110/80

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The Art and Science of Low Carbohydrate Living by Dr Phinney and Dr Volek