DEAR DR. BLONZ: I came across the term “antinutrient” and wanted an explanation of what this means. It was mentioned that they are present in some foods. I have had trouble getting a clear answer. -- S.T., Phoenix

DEAR S.T.: Antinutrient refers to a substance that works in opposition to how a nutrient would typically function. This could involve an interruption in any step from how a nutrient gets absorbed to how the body would eventually utilize it. We often find antinutrients in plants. They can be a part of the plant defenses to deter animals from eating the plants lest they get sick. Antinutrient effects can range from blatant toxic effects to interference with digestive enzymes, to preventing essential vitamins or minerals from being absorbed or working. It’s quite a variety.

For example, a precursor to the deadly poison cyanide is present in some plants, including raw sweet potatoes and cassava. Solanine is a toxic compound produced in green or sprouting potatoes. Raw legumes contain enzyme inhibitors that prevent normal digestion. Grains and legumes contain phytic acid that can bind certain mineral nutrients and inhibit their absorption.

Animals eating such foods in excessive amounts can suffer ill effects, and many learn what to avoid. The risks are less for us if we prepare foods to avoid or deactivate any antinutrients.

Of course, we have more choices of what to eat than animals in the wild. Traditional methods of food preparation tend to take antinutrient foibles into account. For example, raw egg white contains the substance avidin, which binds with biotin, an essential nutrient. Having raw eggs as a regular part of your diet will eventually give rise to a biotin deficiency that can cause scaly dermatitis, referred to as egg-white injury. This malady is first noticed on the skin, perhaps because the skin is our largest and most noticed organ, but if seen on the skin, it is also causing problems throughout the body. This damage is easily stopped by stopping the consumption of raw egg whites.

Antinutrients are present throughout nature; think of them as a method lent by evolution to help plant species survive excessive poaching by insects and animals. Opting for a variety of foods and using appropriate methods of preparation are good strategies to limit the risks of antinutrients. (Read more on antinutrients at b.link/kyw95.)

DEAR DR. BLONZ: In a recent column on canned beans with salt, I was disappointed that you did not mention the option of purchasing frozen cooked beans that can be bought with no salt added. I have seen them at most grocery stores. -- M.L., via email

DEAR M.L.: Sorry for your disappointment. I had mentioned other canned beans as this was what the writer asked about and had in their pantry. I could have added using fresh beans, where soaking is a part of the prep, and I could have also mentioned the option of buying frozen beans, as you suggest. Thanks.

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’m hoping you will weigh in: There’s an ongoing dispute at our house about the importance of a high-fiber diet if an individual is already “regular.” The argument is that fiber is not absorbed, so it provides no nutrients, and there is no need to consume it if you have regular bowel movements. I am having a hard time fighting this argument. -- F.S., San Diego

DEAR F.S.: There is some flawed thinking here that neglects what healthful eating is all about. Similar logic might have you arguing that there is no need to change the oil in your car because it is running fine. You’d face a hefty repair bill with the car, but the issues are more severe with your body.

A similar, and common, mistaken belief is that those on cholesterol-lowering drugs can feast on whatever they want because their medication keeps their blood cholesterol in the “normal” range. I’m afraid that that assumption is not right, and could be potentially dangerous.

Relieving constipation is perhaps fiber’s most notable role. But this nutrient -- yes, fiber is an essential nutrient -- is also associated with a lower risk of heart disease, certain cancers, diabetes, obesity, diverticulitis, hemorrhoids and ulcerative colitis. (For more on fiber, see b.link/j43qu.) All these potential benefits stem from the ability of the fibers in our foods to keep things moving, moderate the absorption of certain nutrients, bind unwanted substances in our digestive system and contribute to the digestive process’s overall health. In recent years, we have begun to study how fiber acts as sustenance to the flora in our microbiome.

At present, the typical American diet contains about 12 to 15 grams of dietary fiber per day, which is about half of what we need. Taking a fiber supplement may work for constipation, but supplements’ ability to achieve fiber’s other health benefits is questionable. Instead, opt for high-fiber foods, including fruits, vegetables and grains. Whole grains are the place to start.

Most people are surprised to learn that whole grains are a more concentrated source of antioxidants than fruits and vegetables on an ounce-by-ounce basis. Although this is principally due to the water weight in fruits and vegetables, it supports the idea that the most healthful way to go is to eat whole foods. Whether fruits, vegetables or grains, we want a food that contains the entire package of nutrients as produced by the growing plant. These components help protect the plant, and they can work their wonders in us, as well.

Finally, for any seeking to increase their fiber intake, do so slowly over a period of days or weeks. With rapid increases, there is a greater chance of side effects such as bloating, cramps, diarrhea and gas. Medications may also be affected, so check with your health professional before adding any fiber supplements to your diet.

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 am researching distance-learning programs in nutrition. My goal is to get educated and then build my own practice, where I can offer individuals nutritional expertise and coaching to help them achieve optimal health, energy and a natural body weight specific to their body type. One place is an academy that is accredited and offers a particular type of diploma in comprehensive nutrition. Do you have any knowledge of schools that provide long-distance training in this profession? -- S.F., New York City

DEAR S.F.: I remain skeptical of distance-learning programs’ ability to provide the training needed to serve as an expert in nutrition, or in any area offering medical advice.

Learning how to provide health guidance is a multi-layered undertaking. Many questions need to be asked, and advice needs to be carefully tailored to each person. The individual’s physician often needs to be in the loop to ensure that medications, preexisting health conditions and other relevant factors are considered.

For example, registered dietitians are given theoretical and specialized training, in addition to their four-year college degrees. They often become part of a medical team working with patients and individuals in real-world situations, with instructors providing the requisite guidance. To retain their registered status, dietitians have to participate in continuing education, and many go on to receive additional graduate degrees.

Whatever you decide, be sure to check the instructors’ and administrators’ credentials at any prospective institution. Seek out those with graduate degrees from traditional brick-and-mortar universities, as well as experience in teaching and research. Their training must be in the areas they teach: Someone having a Ph.D. in the arts, for example, should not be portrayed as an expert or “doctor” in the sciences. Be skeptical of institutions where instructors are primarily graduates from that institution or other distance-learning organizations.

Next, consider what doors, if any, that diploma will open for you. These are undergraduate degrees and may only cover basic concepts. Please don’t get me wrong: It is absolutely essential to understand basic concepts. But the complexities of individuals’ problem situations are what lead them to seek expert advice. The key is to keep learning, and build on that foundational knowledge with experience and expert guidance from appropriately trained instructors.

When I lecture, I often state that most people know more about an automobile or major appliance they’re considering purchasing than they do about things relating to their own bodies, health and well-being. The body is a complex interaction of genetics and life experiences. Diet and lifestyle are important players, but much has to be considered when making recommendations to others. Granted, you don’t need a Ph.D. to decide what to have for dinner, but there is a difference between foods as sustenance and the use of foods and dietary supplements to treat or help prevent a particular problem. Those who would come to you for professional advice will be operating under the assumption that you understand their particular “big picture.”

One of the most important concepts is to appreciate your knowledge’s limits -- that is, to recognize when a particular problem is beyond your training. It is perhaps more important to know what you don’t know, than what you do. Professionals must grapple with this all the time.

I wish you the best, and hope that you can find a program that will move you along the road you seek.

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.