Today, in the fifth part of our life-changing diet series, NHS GP Dr David Unwin explains how going low carb can boost your energy levels and mood, while chef and food writer Katie Caldesi shows you how to bake delicious treats without using heaps of sugar. How often do you reach for something sweet or full of carbs during the day to give you a ‘boost’ — particularly if you are flagging? A lot of the younger patients in my practice (and some older ones!) tell me they often resort to sugary energy drinks for a lift. That’s because most of us associate carbohydrates with energy — and we’re regularly told we need them to give our brain and muscles the fuel they need.