Afternoon Energy Boosters

: Believe it or not, it's completely normal to feel a bit sleepy in the afternoon due to the natural hormonal and temperature changes regulated by our circadian rhythm, also known as our biological clock. 

For a quick pick-me-up that isn't loaded with caffeine, focus on increasing fluids. Try gulping a large glass of cool water or seltzer with a splash of cranberry or mango juice.  If you prefer a hot beverage, a cup of green or herbal tea will also do -- however, test yourself to see if hot or cold beverages work better for pepping you up.

Fruits and vegetables are also a natural source of fluid and can provide energizing vitamin C. Grab a handful of grapes or a medium sized orange.

Sometimes we need energy from food, but try not to load up on high-sugar items as they raise blood sugar quickly. Keep on hand an emergency snack of trail mix made with dried fruit and nuts. Nuts and fruit provide a balance of carbohydrates, fat and protein, which helps give us a boost without a drastic crash in blood sugar afterwards.

Nutritionist Barbara Ruhs, MS, RD, is a licensed registered dietitian, and owner of Neighborhood Nutrition (an education company and private-practice) in Cambridge, Massachusetts. She is also the campus nutritionist at Harvard Business School and University Health Services at Harvard University.