Think of nutrition as the seat on a three-legged stool, with the legs representing proper sleep, activity, and playtime.

Sleep: Doctors recommend at least seven to eight hours per night. Activity: Aim for at least 30 minutes of exercise per day. Playtime: This leg should take up at least 10 minutes per day and might include talking on the phone with a friend who makes you laugh, relaxing, or praying. In addition, try to achieve a two-hour stretch of uninterrupted fun each week to keep your batteries charged.

Got a mental picture of that stool? Good. Now here are some tips for maintaining the strength of the seat.

First, keep away from two big health drains: alcohol and tobacco. As little as one to two drinks per day can cause health problems. And smoking in any amount interferes with the amount of oxygen reaching your brain and increases the risk of a whole host of diseases.

Next, make sure you eat at least every four to five hours while awake. And make sure you're getting enough calories too. Energy in its most basic form is calories. Cutting calories halts our chances of functioning optimally. Taking in more calories may mean slightly slower weight loss, but it feels better and is easier to maintain.

Then, balance your plate. Try to include a palm-size portion of protein-rich food at most meals. Make it chicken, fish, lean meat, eggs, cheese, yogurt, beans, nuts, or seeds and you'll be on the right track. Add another palm-size portion of a starchy food, such as bread, rice, potatoes, or corn. High-fiber choices, such as whole wheat, brown rice, and sweet potatoes with skin, are better than refined carbohydrates such as white bread and sugary treats. Fill the rest of your plate with colorful vegetables and fruit.

A few final tips: Avoid over-salting food and don't overeat -- try to stop eating when you feel about 80 percent full and in 20 minutes, you're likely to feel 100 percent full. Stay hydrated, ask your doctor about taking a standard multivitamin, and remember that in the long run, eating well is critical to sustained energy and overall health.