The nutrition-oriented sites listed here give you reliable, accurate, balanced information: nutritional guidelines, medical news, interactive sites, directories, and more. And these sites are only a start.

U.S. Department of Agriculture Nutrient Database

The USDA Nutrient Database is the ultimate food info chart, with nutrient data for more than 5,000 foods in several serving sizes and different preparations. Each entry is a snapshot of a specific food serving (for example, a raw apple with skin) that lists the amount of

• Water (by weight)
• Food energy (calories)
• Protein
• Total fat
• Carbohydrates
• Dietary fiber
• Minerals: Calcium, iron, magnesium, phosphorus, potassium, sodium, and more
• Vitamins: Vitamin C, thiamin (vitamin B1), riboflavin (vitamin B2), niacin, vitamin B6, folate, vitamin B12, vitamin A, and more
• Lipids: Saturated, monounsaturated, and polyunsaturated fat, as well as cholesterol
• Amino acids
• Other substances, such as caffeine, alcohol, and beta carotene

When you visit this site, the first page that comes up is headlined “Search the USDA National Nutrient Database for Standard Reference.” To find the food you’re looking for, type its name — “apple,” for example — into the empty box below, and then click on Submit.

That brings up a list of possibilities, such as “Babyfood, juice, apple and grape” or “Babyfood, dinner, apples and chicken, strained.”

Ignore the fancy stuff and scroll down to something basic, such as “Apples, raw, with skin.” Click on the circle next to that entry and click on Submit, and a new screen lists various forms of raw apple, such as “100 grams” or “1 cup, quartered or chopped” or “1 large (3-1⁄4" dia) (approx 2 per lb).”

Choose the box in front of the serving you prefer, click on the button marked Submit, and — bingo! There you are — calories and nutrients for one large apple. Neat! To access a list of foods showing the content of a single nutrient such as protein or calories or vitamin C or calcium or beta-carotene, click on the button marked Nutrient Lists from the main page.

Then follow directions to get the list you want, with the foods arranged either in alphabetical order or by the amount of the nutrient in the food. The lists are displayed as PDF (portable document format) files; to read these files, you need Adobe Acrobat Reader.

USDA Food and Nutrition Information Center (FNIC)

Have you worked your way through every single one of the several thousand listings on the USDA Nutrient Database in the previous section? Then come on over to FNIC, which is part of the USDA National Agricultural Library.

To access its info, slide your mouse over to the box on the left side of the homepage and pick a subject. For me, the best are FNIC Resource Lists and Food Composition. The first offers, well, resource lists. The second provides pathways to such nuggets of nutritional data as a report on “Isoflavone Content of Foods.”

Yeah, some of the things pasted here may be much more than you ever wanted to know about, well, the isoflavone content of foods, but for the adventurous, this is a su-pah site. Take a flyer and try it.

U.S. Food and Drug Administration

Entering the FDA Web site is like opening the door to the world’s biggest nutritional-information toy store. So much stuff is on the (virtual) shelves that you hardly know which item to grab first. Luckily, in this store, all the toys are free, and plenty of links to other helpful information mean you can linger here happily for days. Weeks. Years.

Maybe forever. FDA’s charter includes drugs as well as food, so on the left of the homepage, you can click on links to information on medicines for people and pets, poisons and side effects, medical devices (think pacemakers), and products that give off radiation.

The links under Let Us Hear from You, near the center of the page, let activists report on adverse events (“I took that antibiotic and got hives!”) or allow you to contact the FDA with your questions and comments.

For foodies (people who want to know absolutely everything about different kinds of food and food preparation), though, the main event is, well, food.

On the FDA homepage, scroll down the left side and click on Food. Doing so takes you to a page headed “Center for Food Safety and Applied Nutrition” (CFSAN), which is more fun than a barrel of, oh, M&M’s.

The main page of the food section is devoted to Recent News, Program Areas, National Food Safety Programs, Special Interest Areas, and the ever popular Other Sources of Information.

On the left side of the page are links to FDA Documents and sites, phone numbers, and e-mail addresses where you can interact with CFSAN.

American Dietetic Association

This site features nutrition recommendations, tips, guidelines, research, policy, and stats from the world’s largest membership association of nutrition professionals, primarily registered dietitians. The ADA homepage features links to categories (such as Professional Development) that are clearly meant to appeal to association members.

But the site also has tidbits for consumers, such as daily nutrition tips, a monthly feature, nutrition position papers, and an online store where you can find. The niftiest feature on the homepage is the link to Find a Nutrition Professional.

Click on this link and you gain access to the ADA’s Nationwide Nutrition Network, a referral service that links consumers, doctors, food companies, and restaurant people with dietetic professionals. ADA’s mission is to serve the public by promoting nutrition, health, and well-being.

If you can bend your brain around the much-too-adorable net address (“eatright”? Give me a break!), you’ll discover this site is a true treasure trove. And golly gee, who wouldn’t love having a personal dietitian to lead the way through the maze of conflicting nutritional advice?

American Heart Association

This site tells you everything you ever wanted to know about diet and heart disease. Starting at the homepage, run your mouse down the left side to Healthy Lifestyle.

Click on it — and then click on Diet & Nutrition. Up pops a page with features such as the American Heart Association No-Fad Diet, Delicious Decisions, Nutrition Facts, Dietary Recommendations, and Shopping Made Simple.

The indisputable link between diet and heart disease risk, not to mention the AHA site’s user-friendly approach, makes this a must-stop on your nutritional tour of the Web.

American Cancer Society

The ACS Web site is dedicated primarily to information about cancer: definitions, treatments, research, and support services. True, most of the nutrition news you find here is available elsewhere, but this site’s defined focus provides easy access to other cancer-related topics.

On the ACS homepage, type “diet” into the Search box at top. Bingo! You’ve opened a grab bag of ACS press releases, guidelines, and the most common questions people ask about food and cancer (with answers).

More-targeted searches — such as “high-fiber food” — yield more-specific responses, such as information on whether dietary fiber is related to a lower risk of colon cancer. Until now, the American Cancer Society was barely a blip on the screen of nutrition sources.

Today, with a growing number of well-designed studies to demonstrate that some foods and diet regimens may reduce your risk of certain types of cancer while others put you in harm’s way, the ACS Web site offers solid reporting on this area of nutritional research.

Food Allergy and Anaphylaxis Network

The Food Allergy and Anaphylaxis Network (FAAN) is a nonprofit membership organization (membership fee: $30/year for individuals) whose participants include families, doctors, dietitians, nurses, support groups, and food manufacturers in the U.S., Canada, and Europe.

The group provides education about food allergies in addition to support and coping strategies for people who are allergic to specific foods.

From FAAN’s homepage, you can link to updates, daily tips, newsletter excerpts, and all the usual service-oriented goodies. The site’s best feature — an e-mail alert system — is free. Click the link under Special Allergy Alerts, fill out the form, and submit it to the site.

You’re now connected to an early warning system with allergy-linked news and information about recalls of troublesome products, such as 2-ounce bags of cashews that may mistakenly contain peanuts.

This no-nonsense, highly accessible site is required reading for people with food allergies. Others, such as families and friends, can also benefit from its solid information and support services.

International Food Information Council (IFIC)

The International Food Information Council (IFIC), created in 1985, is a nonprofit organization dedicated to improving the relationship between the nutrition community — scientists, food manufacturers, health professionals, government officials — and the news media.

Although the council’s membership includes corporations that make and sell food products, IFIC plays no role in marketing products or promoting its members. Its aim is to make sure that consumers get accurate information about diet and health. The IFIC homepage allows you to access features in English or Spanish.

Consumers can bypass the professional stuff and head for links under Nutrition and Food Safety Information or click on the “Food Insight Newsletter” or the terrific Glossary of Food-Related Terms. The site also offers articles on basic nutrition topics, such as functional foods, oral health, dietary fats and fat replacers, and additional resources.

The writing is accessible, the information impeccable. IFIC is a trade group, so purists may complain about some IFIC positions, such as its endorsement of some food additives, but the site’s intelligent approach to complex and emotional issues allows you to make up your own mind.

American Council on Science and Health (ACSH) and the Center for Science in the Public Interest (CSPI)

The American Council on Science and Health and the Center for Science in the Public Interest are two nonprofit consumer-friendly organizations that usually sit on opposite sides of any nutritional issue. ACSH is cool and calm; CSPI is a hot-button advocate.

For example, CSPI believes many additives are hazardous to your health; ACSH says some additives are useful in some foods for some people. This kind of disagreement ensures that if you punch up the same search word or phrase on both sites, you’ll find out about the pros and cons of an issue.

Both sites feature news releases, position papers, online membership enrollment, order forms for publications, and links to other sites. Which site you prefer is pretty much a matter of personality, but you can’t go wrong with either one if you’re looking for highly reliable information about nutrition issues and how food and diet affect your health.