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One of the main mechanisms behind low-carb diets is a reduction in insulin levels (3, 4).
Insulin has many functions in the body, such as telling fat cells to store fat.
But another thing that insulin does is to tell the kidneys to hold on to sodium (5).
On a low-carb diet, your insulin levels go down and your body starts shedding excess sodium and water along with it. This is why people often get rid of excess bloat within a few days of low-carb eating.
However, sodium is a crucial electrolyte in the body and this can become problematic when the kidneys dump too much of it.
This is one of the main reasons people get side effects on low-carb diets… such as lightheadedness, fatigue, headaches and even constipation.
The best way to circumvent this issue is to add more sodium to your diet. You can do this by adding more salt to your foods, but if that doesn’t suffice then you can drink a cup of broth every day.
I personally like adding a bouillon cube into a cup of hot water, then drinking it like a soup in a cup. It actually tastes really good and supplies 2 grams of sodium.
Bottom Line: Low-carb diets lower insulin levels, which makes the kidneys excrete excess sodium from the body. This can lead to a mild sodium deficiency.