AMERICANS ARE notorious snackers. From raw broccoli to beer nuts, we reach for bits of things that come wrapped in cellophane and tucked into Baggies. We forgo breakfast for coffee and a doughnut; we snack on saltines and munch on hickory flavored almonds. We go for chips and pretzels and peanut butter crackers--all usually a small hike away in a strategically placed vending machine. Whatever we can reach for we can snack on.

This undermines another American penchant--the calorie-counting compulsion. Perhaps we snack because it relieves us of the responsibility of counting the scores of calories we unwittingly consume.

But there are those who want to snack and count, those who refuse to give up the foods they love for the sake of a diet, and those who want to know the nutrient density of their snacks.

For snack fans, we provide a chart on Page E19 of common snack items in easy-to-remember 100-calorie portions. From Oreos to carrot sticks, a nutrient data chart shows exactly how dearly we pay for munching.

You needn't be a nutritionist to figure out what tops the list of snacks for nutrition density. You get more for your 100 calories with bananas and apples than you do with a glazed doughnut. But there is a little news.

Foremost, beer drinkers will be vindicated. Eight ounces of their favorite brew leaves cola drinkers in the dust, nutritionally speaking. Even those virtuous carrot sticks can't offer the niacin that beer packs. On the other hand, while 3 1/3 carrots weigh in at 100 calories, many sound diet plans offer them as a "free food" because of their caloric insignificance.

Also, two of America's favorite candies sit back to back with results that are not surprising, but reassuring. Milky Ways, true to their name, are higher in calcium than Reese's Pieces; the latter, on the other hand, is flavored with peanut butter, which means it's higher in protein. About two bites of Milky Way fill out the 100-calorie criterion. A small handful of Reeses Pieces does the same--E.T. probably has a higher metabolism than folks of this terrestrium.

The news gets worse, however. Think of the Triscuits you may have packed away at the last cocktail party. They add up quickly--five equal 100 calories. Goldfish crackers, too, are high in calories--many of which come from fat. A package of cheese and peanut butter crackers that sustains many of us through an afternoon lull at work contributes 200 calories to our daily intake. We should eat only three and put the rest in a drawer for tomorrow.

It's disheartening to realize we reach our 100-calorie limit before we've reached the bottom of our one-ounce vending machine package of potato chips. And 8.5 pretzels disappear quickly as we watch Earl Weaver lead the Orioles through the pennant race. Even granola bars, which come disguised as health food, are loaded with calories and very little else. But, what the heck, that makes it easy to rationalize reaching for the oatmeal cookies instead. At least you get 1 1/2 of those.