From everything I read on the V-Diet people swear to get sick because of the lower calorie intake on the V-Diet. Meaning, they think their immune system is compromised to the point where they catch a cold etc. I have a different perspective on this.
You are having carbohydrate and calorie withdrawl. Your body is fighting you on the lower calorie intake and lack of carbs the brain would desire to operate without using ATP.
I have experienced this on EVERY Velocity Diet I have done (5 total now) and it is brutal every time. Around the end of the first week (if you give your body rest) you start to feel better.
I just want to ATTEMPT to debunk the myth that you get sick on the V-Diet because your immune system is compromised.