DEAR DR. BLONZ: At last year's annual physical, I learned that my triglycerides were over 400. Over the past year, I have been losing weight, and I also started medication for high blood pressure and high triglycerides. My levels are on the way down, but can you tell me exactly what triglycerides do in the body? -- T.L., Teaneck, New Jersey

DEAR T.L.: The role of triglycerides often confuses people. That's not surprising, given the speed with which many complex health terms have encroached upon our daily lives. The triglyceride can be thought of as the body's most concentrated package of stored energy. It is composed of three fatty acids attached to a 3-carbon (glycerol) structure, and can be a fat or an oil.

Fats and oils are usually differentiated by their states at 68 to 72 degrees F, the range referred to as "room temperature." Fats, such as butter or lard, will be solid at room temperature, while oils, such as olive, corn or canola oils, are liquid. (This definition has some wiggle room: Coconut oil, while solid at room temperature, has managed to cling to its "oil" name.) That being said, the term "fat" is generally used to refer to both the fats and oils in the foods we eat.

Triglycerides include the fats in our food, those traveling in our bloodstreams and those hanging around in the body's excess energy storage areas -- and we all know what that means.

We take in energy when we eat, after which our blood triglyceride level rises -- even if there's a limited amount of fat in the meal. This is because the body is programmed to avoid any waste of calories (energy), even if in the form of protein or carbohydrate. Excess energy will be converted into fatty acids by the liver, and then be packed into triglycerides and released into the bloodstream on its way to storage. Food fats are already in the form of triglycerides, but during digestion they are disassembled, only to be put back together after absorption. A high intake of alcohol or of sugars such as fructose, sucrose or glucose tends to increase the blood triglyceride level.

To get an accurate read on one's baseline triglyceride level, tests are usually given after a 12- to 14-hour fast. There can be lab-to-lab differences on what comprises a normal range for blood triglycerides, but generally speaking, levels above 200 milligrams per deciliter are considered high. You can read more about this at tinyurl.com/zps6kf5.

High triglycerides are now recognized as a risk factor for heart disease, which makes perfect sense when you think about it. Simply put, it is not in our best interest to have higher-than-normal levels of fats roaming around our bloodstreams. A high triglyceride level may be more of a risk factor if accompanied by an elevated blood cholesterol level.

Finally, let me offer my congratulations on your strides toward health. High triglycerides are more common in people who carry excess weight, so I wish you success in your continued efforts.

Send questions to: "On Nutrition," Ed Blonz, c/o Universal Uclick, 1130 Walnut St., Kansas City, MO, 64106. Send email inquiries to questions@blonz.com. Due to the volume of mail, personal replies cannot be provided.

DEAR DR. BLONZ: Forgive the basic nature of this question, but what is the difference between a vegetable and a fruit? Also, I am interested in becoming a Certified Dietary Manager. How would I go about this, and what are the requirements? -- R.K., Indianapolis, Indiana

DEAR R.K.: A vegetable is an edible part of a plant that has a soft stem. These parts can include leaves (such as lettuce), roots (carrots), bulbs (garlic), stalks (celery), seeds (peas), tubers (potatoes) and flowers (cauliflower). A fruit is the mature ovary in a flowering plant: the fleshy part of the plant that contains the seeds. This means that tomatoes, eggplant, peppers and squashes are technically fruits, even though they are commonly thought of as vegetables.

There was actually a Supreme Court decision in 1893 stating that a plant part typically eaten with the main course was a vegetable, while a plant part typically eaten as an appetizer or dessert was a fruit. (The clarification was sought by a tomato importer looking to avoid vegetable tariffs by classifying his wares as fruit.) I wonder what those justices would say if they had a chance to savor today's cuisines, many of which make use of fruits throughout the meal.

As for your interest in becoming a Certified Dietary Manager, there are a number of resident and correspondence schools that offer training. After that, gaining and maintaining certification means meeting certain career requirements and passing a nationally recognized credentialing exam. For more information, check the site for the Certifying Board for Dietary Managers: cbdmonline.org.

DEAR DR. BLONZ: What is maltodextrin made of? I have called a soup company, two cereal/bread companies and two nutrition stores, and no one knows. I ask because my grandson is allergic to barley. We associate the word "malt" with grains, so we have omitted any product with maltodextrin from his diet, just to be safe -- and it's in a lot of products. I am hoping you can tell me exactly what it is. -- M.S., Sun City, Arizona

DEAR M.S.: Maltodextrins are easily digestible carbohydrates made from starch. The starch is cooked and then broken into smaller pieces -- similar to what happens when starch is digested. As additives, maltodextrins serve as texturizers or flavor enhancers. According to FDA regulations, manufacturers should use use corn, potato or rice as the source of the starch for any maltodextrins used in foods. Note that this may not be the case for maltodextrin used in medications.

Where allergies are involved, it is best to use caution; even though there are regulations, there is no guarantee that a particular manufacturer won't use a different source for its starch. For any specific products your grandson might consume, you should consider contacting the manufacturer and requesting further information about their maltodextrin supplier.

Send questions to: "On Nutrition," Ed Blonz, c/o Universal Uclick, 1130 Walnut St., Kansas City, MO, 64106. Send email inquiries to questions@blonz.com. Due to the volume of mail, personal replies cannot be provided.

DEAR DR. BLONZ: There are a number of weight-loss teas at my drug store, and I was wondering which, if any, are worth consideration. -- S.C., San Jose, California

DEAR S.C.: As a basic concept, consuming liquids with (or before) a meal can help you feel fuller, and can therefore cut down the volume of food you eat. While many claim to have special metabolic powers, "weight-loss teas" usually rely on this most natural phenomenon to accomplish their goal.

Some such products might include herbal diuretics, such as couch grass, buchu, dandelion, uva-ursi and butcher's broom. The taking of a diuretic tea can decrease the total amount of water in the body, which will impact the numbers on the scale. But it is only water you are losing, not excess body fat. What's worse, it tends to be a short-term effect, with the water weight usually returning once the regimen is stopped.

Tea is a great beverage, and we are learning that some of the compounds found in green, black and oolong teas offer health benefits. That should be the motivator for drinking it -- not the promise of weight loss. Dramatic claims of success should be viewed with great skepticism.

One product I recall came in a package that displayed a slim woman on the front. The literature indicated that drinking the tea would facilitate the shedding of unwanted weight, but the product was nothing more than a plain black tea of modest quality. If you looked inside the package, there was a piece of paper that explained that you had to eat less and exercise more for the weight-loss plan to work. What a novel approach.

DEAR DR. BLONZ: Have you written about noncaloric sweeteners such as stevia and sucralose? Some of my friends are concerned about the safety of these sweeteners. -- S.S., Portland, Oregon

DEAR S.S.: Sugar substitutes provide few or no calories and have minimal effect on blood sugar, which is a plus for people with diabetes. Then there is the fact that they do not contribute to tooth decay. But while a sugar-substituted dessert, for example, succeeds in putting fewer calories on the plate, there is no reliable evidence that it works as a weight-loss strategy.

A paper by Richard Mattes in the 2009 American Journal of Clinical Nutrition reported that the addition of noncaloric sweeteners to diets posed no benefit for weight loss, or reduced weight gain, unless accompanied by energy (calorie) restriction.

I refrain from encouraging the consumption of noncaloric sweeteners -- not because they are necessarily dangerous, but because I don't encourage seeking out excessive sweetness. The Berkeley Wellness letter has a simple and straightforward piece on the various options: tinyurl.com/zxwf6zs.

Send questions to: "On Nutrition," Ed Blonz, c/o Universal Uclick, 1130 Walnut St., Kansas City, MO, 64106. Send email inquiries to questions@blonz.com. Due to the volume of mail, personal replies cannot be provided.