Water: Few people — whether active or not — drink sufficient water, and side effects of even slight dehydration include headaches, fatigue and low concentration levels. Yet increasing fluid intake can increase energy levels, aid digestion, give skin a boost and help boost your anti-aging armoury. Concentrate on drinking little and often throughout the day, being extra vigilant after exercise or when you've been confined in a dry, overheated or air-conditioned environment.
