DEAR DR. BLONZ: A recent blood test showed that my cholesterol levels were fine, but my triglycerides were slightly elevated. You mention them periodically, but please explain what triglycerides are and the role my diet might be playing. -- F.L., Oakland, California

DEAR F.L.: The role of triglycerides often confuses people. That's not surprising, given the speed with which complex health terms have encroached upon our daily lives.

Think of triglycerides as the body's most concentrated form of stored energy. (For this discussion, think of the terms "fats" and "triglycerides" as compatible.) The human body is designed to be mobile and to conserve energy. Triglycerides are the form into which excess energy is converted, and also the way they get packaged for transport and storage.

Contrast this with plants, where the mission is to grow rapidly; energy in plants gets made into carbohydrates, which serve as a building material. (If we stored energy as carbohydrates, we would be too bulky to move.) The fascinating shift in plant life is with their seeds, where their light weight allows them to travel on the wind or with animals to land -- and grow -- in a new area. In seeds, energy is stored as fat.

A list of triglycerides would include the fats in our diet (butter, cooking oils, etc.), those in our bloodstream, and the fat that eventually makes its way to the body's energy storage depots. All triglycerides are built like a squat version of the letter "E," where the three prongs are individual saturated or unsaturated fatty acids attached to a glycerol backbone.

There is a big difference between triglycerides and cholesterol. Cholesterol is a waxy, fatlike substance with a complex structure that looks a small piece of honeycomb. Cholesterol is not used for energy; it is a structural element in all cells and serves as a raw material in making many hormones.

Both triglycerides and cholesterol are members of the lipid family. In addition, both travel through the body in packages known as lipoproteins. And finally, both share the dubious distinction of having their elevated blood levels associated with an increased risk of heart disease.

The blood triglyceride level usually goes up after eating, even if there's a limited amount of fat in the meal. This occurs because the body is programmed to convert excess protein or carbohydrate into triglycerides, the form of energy best suited for transport and storage. Consuming alcohol or excess sugars such as fructose, sucrose or glucose will also increase triglycerides.

Should you be concerned about your triglyceride level? As blood tests for triglycerides are typically taken after a fast, any effects from your last meal should be over. Given this, if you still have an elevated triglyceride level, it would be something to be discussed with your health professional. Much will depend on your health profile and history. You and your doctor will decide whether this is something to be monitored or if additional tests may be needed to rule out any ongoing problems.

Read more about conditions that can elevate triglycerides at b.link/r34n7r.

Send questions to: "On Nutrition," Ed Blonz, c/o Andrews McMeel Syndication, 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: I eat a few eggs almost every week. Lately, I'm seeing more types at the store that include omega-3 fats, which I had thought were only in fish. I wanted to know more about this. How much omega-3 do you get in these eggs, compared to what we need? -- T.T., Mesa, Arizona

DEAR T.T.: Some background first: Fats are long chains of carbon atoms. The name "omega-3" refers to the location of the first double bond -- in this case, the third carbon (3) from the end (omega) of the chain.

There are three different essential omega-3 fats in human nutrition: ALA (alpha-linolenic acid), EPA (eicosapentaenoic acid), and DHA (docosahexaenoic acid). They are all considered essential because they are needed to support normal health, and we can't make them on our own.

ALA is in plant oils, including flaxseed, canola, soy and walnut. More well-known omega-3s include the longer-chain EPA and the even-longer-chain DHA, both found in fish and other seafood. Omega-3 fats are often collectively called "fish oils," but this is inaccurate since plant-sourced ALA does not come from fish.

Our metabolism has a chain-lengthening mechanism that allows it to convert ALA into EPA and DHA. This capability is important for vegetarians and for anyone who doesn't eat seafood. However, this "lengthening" mechanism is inefficient, with only a fraction of ALA getting converted to EPA and DHA. While some makes it, most ALA in the diet gets burned for energy. Vegans should pay attention to their ALA intake or consider taking a supplement (more on this at b.link/4bfyqq).

Omega-3-enriched eggs will have a higher content of these fatty acids, but you must read the label to determine the type present in any particular brand. If the hens' feed was enriched with flaxseed meal, the eggs would have increased levels of ALA, and a slight amount does get lengthened into EPA and DHA by the hen's metabolism. Some brands enrich the feed directly with EPA and DHA from fish oil or marine algae. In those instances, the eggs will have higher levels of the longer-chain omega-3s, but still only a fraction of what you get from fish sources. As with any specialty eggs, enriched ones will cost more.

The amount in omega-3 enriched eggs can vary, so, again, read the label; one popular brand provides 125 milligrams per egg, which is only a fraction of that in seafood. The American Heart Association recommends 1 gram daily of DHA and EPA for overall heart health.

For reference, the richest sources of EPA and DHA are cold-water fatty fish such as salmon, mackerel, herring, sardines and anchovies, and other seafood, including oysters and caviar. (For more on fish, including a chart of levels, see b.link/bbv3ze.)

Send questions to: "On Nutrition," Ed Blonz, c/o Andrews McMeel Syndication, 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: Do we need to "flush" our digestive system and detox/cleanse our liver routinely? I ask because of the many posts I see on social media about this, most of them making a case for special products and fasting regimens. The argument presented is that doing a routine cleanse gets rid of toxins that would otherwise build up in the liver and form crusts in the folds of the intestines, making digestion less efficient. The situation is described as being responsible for common digestive ailments and general health problems, and also as affecting the function of our immune system.

They make a good case, and I wanted to give the regimen a try, but my physician said it's a bunch of nonsense. -- S.F., Tulsa, Oklahoma

DEAR S.F.: This is a common question, perhaps due to all that marketing. I compliment you for checking with your physician before making a purchase or beginning a drastic "cleanse."

I admit that being able to "flush toxins" out of the body is an attractive concept -- especially if there are ongoing health issues and this is positioned as the fix you need. Wouldn't it be great if there was objective evidence it could work as it claimed?

Toxins and undesirable compounds tend to be eliminated from the body via our excretory system, which includes the liver, large intestine, lungs, kidneys and skin. That is how our systems evolved to protect us from exposure to unwanted substances; humans might not have lasted this long if these systems were that faulty.

Elimination often begins with a step to reduce the potential risk of the substance, such as a detoxification reaction and/or dilution to help reduce the concentration of harmful elements. Unwanted fat-soluble and water-soluble compounds are distributed in the appropriate body compartment while waiting to be shown the door.

Some "detox" products and programs involve fasting, but this may not work as advertised. When we reduce our eating, or stop altogether, the body is programmed to pull fat from its storage areas to provide the energy we need. So those unwanted substances, shoved out of the way while waiting for elimination, will get pulled back into the blood. Studies have found that the blood levels of fat-soluble toxic substances such as DDT will actually increase during a fast.

The fatigue, aches, dizziness, anxiety, lethargy and other symptoms you experience during a fast are probably not signs of your body casting off toxins, as you may have been told. Instead, in a toxic twist, these symptoms can be byproducts of the stuff released as your energy-deprived body breaks down stored fat to get its needed calories.

Next, consider that our liver cells, like most others in the body, get constantly remade: Your liver is not made up of the same cells it used last year. And the cells lining your intestines get replaced every week, which casts doubt on those fears that we develop crusty insides if we don't detox.

While the promise of a quick-fix detox is attractive, a more reasonable strategy is to keep your body well-hydrated and nourished with a healthful selection of plant-based whole foods. This provides a constant intake of nutrients and protective compounds to keep your systems working. Complement this with an active lifestyle to keep blood and fluids flowing to all corners, and you'll help keep all things in tune and cranking along.

Send questions to: "On Nutrition," Ed Blonz, c/o Andrews McMeel Syndication, 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.