Nutrition Basics

How Calories Count

Losing, gaining or maintaining your weight depends on many factors. One factor is how many calories you take in and use up during the day. It's a concept called "energy balance". Generally,

  • If you eat more than your body needs to perform your day's activities, you store the extra calories as fat.

  • If you don't take in enough calories to meet your body's energy needs, your body will use the stored fat as fuel.

However, more than just the number of calories you consume matters. For instance, a calorie from soda affects our bodies very differently than a calorie from a walnut. The soda is quickly absorbed into our blood stream as sugar, raising blood sugar and insulin levels. This quick rise can cause the sugar to be stored as fat. A calorie from a walnut provides energy from protein or fat, which takes longer to digest and do not have the same quick blood sugar increasing effect as the calorie from sugar. The energy/calorie from a walnut may be used for energy, rather than stored.

Both food quality and number of calories consumed matter.

Quality of Calories

“Eat food. Not too much. Mostly Plants.” - Michael Pollan

To improve your overall health and wellness, focus on eating more whole foods that will nourish your body and eating less food that provides little nutritional benefit, like packaged junk foods and sugar sweetened beverages.

Look beyond the exact number of calories consumed, and putting more stress on where these calories are coming from is important to improve your overall health and wellness. That is, focus on eating more whole foods that will nourish your body and eating less food that provides little nutritional benefits.

When choosing food items, keep sodium, added sugar, saturated fat, and trans fat levels as low as possible. Some examples of foods to limit are packaged junk foods, and sugar sweetened beverages. Aim to eat plenty of fiber, protein, and healthy fats from whole foods. This means eating foods like fish, nuts, seeds, and avocados.

To improve your nutrition, adopt these healthy practices:

  • Incorporate at least one fruit and/or vegetable at every meal.
  • Eat foods that don’t have a package or food label like fruits, vegetables, dairy and grains.
  • Replace soda and sugary drinks with water and/or seltzer.
  • Shop the perimeter of the grocery store.
  • Buy frozen fruits and vegetables to cut down on cost.
  • Make extra portions of home cooked foods to bring for leftovers instead of eating out.


Getting a good night’s sleep is important for your physical and emotional health. Quality sleep plays a crucial role in boosting your immune system, enhancing your mood levels, and keeping you alert. Getting the ideal 7.5-8.5 hours of sleep each night helps you retain new information, and allows your body to recharge, so you can feel energized and prepared to tackle the day ahead. If you are looking to lose weight or maintain your current weight, a good night’s sleep is essential. Research shows chronic sleep deprivation may alter levels of hormones that affect your appetite and can ultimately lead to weight gain.

Sleep hygiene is defined as a variety of practices that are necessary to have quality sleep at night and in turn, full daytime alertness. You can improve your sleep hygiene by following these helpful tips:

  • Go to sleep and wake up around the same time every day - even on the weekends.
  • Avoid stimulants such as caffeine, alcohol, and cigarettes close to bedtime.
  • Exercise for 20-30 minutes each day, but avoid vigorous physical activity late at night, which can increase alertness and keep you awake.
  • Steer clear of spicy, heavy, and/or large meals late at night. These foods can cause uncomfortable indigestion and/or heartburn that make it difficult to fall asleep.
  • Use your bed for sleep and sex only. This will strengthen your association between your bed and sleep.
  • Adjust your bedroom temperature so that you are cool and comfortable.
  • Establish a relaxing ritual before bed, like reading a book or listening to music. This will create a separation between the stresses of your day and bedtime.
  • If your mind is racing with thoughts, ideas, and tasks you need to do the next day, jot them down before bed. Getting your thoughts on paper will get them out of your mind and help you relax.
  • Keep your bedroom quiet, and if necessary wear earplugs to block out noise.
  • Avoid napping too close to bedtime, and limit naps to 20 minutes.

If you are having trouble falling asleep night after night, or if you are always feeling tired the next day, you may have a sleep disorder and you should see a physician.

Sources: Brigham and Women’s Hospital Division of Internal Medicine; Massachusetts General Hospital Primary Care Operations Improvement


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