Hydration Has a Major Effect on Energy Levels and Brain Function

Your brain is strongly influenced by hydration status.

Studies show that even mild dehydration (1-3% of body weight) can impair many aspects of brain function.

In a study of young women, a fluid loss of 1.36% after exercise impaired both mood and concentration and increased the frequency of headaches .

Another similar study, this time in young men, showed that fluid loss of 1.59% was detrimental to working memory and increased feelings of anxiety and fatigue .

A 1-3% fluid loss equals about 1.5-4.5 lbs (0.5-2 kg) of body weight loss for a 150 lbs (68 kg) person. This can easily occur through normal daily activities, let alone during exercise or high heat.

Many other studies, ranging from children to the elderly, have shown that mild dehydration can impair mood, memory and brain performance .

Bottom Line: Mild dehydration (fluid loss of 1-3%) can impair energy levels and mood, and lead to major reductions in memory and brain performance.