With winter weather setting in and final exams approaching, many students are worried about staying energized and healthy. Nutrition experts say the key is to eat a well-balanced diet that includes vitamins, minerals and the proper amount of calories.

Margherita Cantorna, assistant professor of nutrition immunology, said the best way to do this is to use the food pyramid as a guide.

The food pyramid is based on U.S. Department of Agriculture dietary guidelines and shows the appropriate servings of an ideal diet based in grains, fruits and vegetables, meat and dairy, and oils and sugars, she said.

She said micronutrients, which include all vitamins and most minerals, are only needed by the body in small amounts but are necessary for reducing the risk of illness, among other things.

"Micronutrients are required by the immune system for proper functioning, such as making cells and enzymes and [carrying out] certain processes," she said.

Namanjeet Ahluwalia, associate professor of nutrition, recommended getting at least five servings of fruits and vegetables a day and making sure the servings are varied in color to ensure that the body gets many different vitamins and minerals.

She said macronutrients, which include proteins, carbohydrates, fats and water, are also needed, but in larger amounts, to provide the body with energy and to boost the immune system's ability to fight infections and diseases.

"If someone is under-nourished or has a deficiency of any of these nutrients, [his or her] immune response may be reduced," she said.

Melissa Martilotta, instructor of nutrition and director of Penn State's nutrition clinic, said all foods contain energy, but the best way to get energy is by eating plenty fruits and whole grains because they contain carbohydrates, which are most easily broken down into energy.

"Fresh fruits are especially good because they have more vitamins, minerals and fiber," she said.

Carbohydrates break down into sugars, which are transported to any parts of the body that require energy, such as muscle cells while a person is exercising, she said. Martilotta also said it is important to make sure the body is receiving enough calories because if not, it will be more susceptible to illness.

"Many students eat too few calories, especially if they are vegetarians or if they are dieting because [the body gets] little protein," she said. "Protein is important because it is the building block of all body chemicals."

However, she said she does not recommend high-protein diets.

She also does not recommend vitamin and mineral supplements unless a person has a specific deficiency, because if one relies too heavily on these supplements, he or she will not be getting other substances that food provides and the body needs.

"There are benefits of food above and beyond vitamin and mineral content," she said.

She explained that certain substances called free radicals enter the body through the skin and are often harmful to one's health. One such substance is ultraviolet light, which can lead to cancer.

Some epidemiologists believe other free radicals may cause heart disease, diabetes, and aging. However, many foods, particularly fruits and vegetables, contain plant chemicals which act as antioxidants that trap and neutralize free radicals.

"You have to get what you can from food, not vitamin and mineral pills because you will miss out on the plant chemicals," she said.

Ahluwalia said supplements might be necessary if a person is deficient in certain vitamins or minerals, but this is a condition that should be determined by a physician or dietitian. She suggested that students meet with a counselor at the nutrition clinic rather than attempting to assess the adequacy of their diets on their own.

Penn State students, faculty and staff who need help balancing their diets can get free individual counseling at the nutrition clinic, located at 235 Ritenour Building and 121 South Henderson Building. The counselors are mostly graduate students and seniors majoring in nutrition and are available to answer nutrition-related questions and concerns, Martilotta said.

"The counselor will analyze [the client's] diet and lifestyle and then make suggestions to improve it according to [the client's] goals," she said.

Heather Bainbridge (senior-nutrition), a counselor at the clinic, said goals of clients range from managing vegetarian diets to losing or gaining weight to curing stomach problems.

One can request an appointment by filling out the clinic's history forms, which ask for the person's goals and concerns, medical and dietary histories, eating habits, lifestyle, and available times to meet with a counselor. The forms can be found online and at both of the clinic's offices.

The information given in the history forms allows the counselor to prepare for the initial appointment, during which the counselor will go over the client's past and give basic nutritional tips, such as a recommended number of calories to eat every day, Bainbridge said.

"There is actually an equation that specifies the amount of calories to eat per day, based on [the person's] weight, height and age," she said.

She said she provides her clients with pamphlets and handouts, including suggested "grocery lists" of healthy foods and exercise guides. Clients may later opt for follow-up appointments to discuss their progress and obstacles to future progress with their counselors.

Bainbridge said she always reminds her clients that even small amounts of progress are indications of success.

"Any improvement is awesome because it's hard to change something you're used to doing," she said.

Bainbridge was a counselor at HealthWorks, which is not affiliated with the nutrition clinic, during her sophomore and junior years. However, she feels she is able to help clients more at the clinic because the appointments are on a one-on-one basis, whereas at HealthWorks the clients meet in groups.

"[At the clinic] it's really personalized and it's more motivating because [the clients] are more able to apply it to their own lives," she said.