(The New York Times News Service) -- Dear Healthy Professor: Which is worse; too much sugar or too much fat?

Answer: Too much of either one isn't good.

Sometimes, we try to make a better choice between a food that's high in fat and one that's low in fat but may be high in sugar. I witnessed this situation between a mom and her two little girls who stopped for a snack at a Starbucks. The girls wanted something sweet to eat and they were allowed to choose the reduced-fat cake, a marshmallow bar or a mini-donut.

The mom explained that the other choices were high in fat and therefore bad for their heart. (Times have changed. When my kids were that age, I explained why they shouldn't eat play-doh.)

I continued to observe this family and was curious about the nutritional values of their selections. (I'm not a stalker, just doing my job.) The reduced-fat cake has 340 calories, 9 grams of fat and 40g of sugar. The cake the 5-year-old really wanted has 350 calories, 13g of fat and 34g of sugar. Not much of a difference. I am concerned with the calories of these choices, a lot for a little kid.

Big sister chose the marshmallow bar with 210 calories, 4g of fat and 15 grams of sugar, a better choice under the circumstances.

The mini donut has 120 calories, 6g of fat and 10g of sugar; not too bad for a sweet snack. All these treats lack nutritional value for the calories, which is reason enough to limit their consumption.

Although fat has long been touted the culprit we know when it comes to heart disease, there's fat and there's fat. The saturated fats like those in meats and dairy products should be eaten sparingly. These kinds of fats also find their way into desserts and processed foods.

Other fats like those from plant oils, nuts and some fish should have a prominent place in our diet since they have been found to help lower cholesterol, fight inflammation and increase our satisfaction. Whatever the source, all fats are nine calories per gram and should be consumed in moderation to control calories.

Sugar is fast becoming a major health problem. So much so that the American Heart Association just released new guidelines for limiting added sugar in our diet.

Added sugar means what's added to foods and does not include the sugars naturally found in fruit and dairy products.

So what are the new recommendations? Brace yourself.

Women should aim for 100 calories per day (6 1/2 teaspoons or 25 grams) and men should aim for 150 calories per day (9 1/2 teaspoons or 38 grams). Considering that 16 ounces of sweetened ice tea can have 12 teaspoons of sugar, you can see how fast the sweet stuff adds up.

There are all kinds of sugars. Some with good reputations (like honey and molasses) and some that have been on the nutrition hit list (like high-fructose corn syrup). Truth is, it's all pretty much the same, and excess dietary sugar (especially from sugary drinks) is associated with the rise in obesity.

To add insult to injury, it seems that the more sugar we eat, the more we want. That's why desensitizing your sweet tooth may be the best thing you can do. Artificial sweeteners are not the answer. They keep us wanting more, and in some cases their safety is still a matter of debate.

Don't be fooled. Read labels, ask or look up the nutritional value of foods you suspect to be high in sugar and fat. When in doubt, eat half. It's your choice.

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