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.

DEAR DR. BLONZ: You often mention the benefits of eating fish like salmon or sardines, which are high in omega-3 fats. But does this recommendation hold if you are on anticoagulants? I have deep vein thrombosis, and have been taking Coumadin. As part of my treatment, I go in regularly to measure my “bleeding time.”

I cook and eat fish periodically, and have taken a fish oil supplement for many years. But during a recent call with friends, they warned me that it could be dangerous, and that I should avoid all omega-3 fats from fish or supplements. Since I know these are essential nutrients, what do you advise? -- S.P., Chicago, Illinois

DEAR S.P.: Bottom line up top: If you are taking an anticoagulant such as Coumadin, you need to take care when making changes to your habitual intake of omega-3 fats. That does not mean you should stop or avoid them; the key is to be careful when making changes to your routine intake -- whether increasing or decreasing. Let me explain.

The omega-3 fats at issue include EPA and DHA (eicosapentaenoic acid and docosahexaenoic acid, respectively), which are found in fish and other seafood. These have a shorter cousin, ALA (alpha-linolenic acid), which is found in plants. The body has metabolic pathways that turn ALA into EPA and DHA, but it’s not an efficient process. Most omega-3s of plant origin get used or stored for energy, with only a small fraction being converted into EPA or DHA.

The significance here is that bleeding time -- the tendency and time for one’s blood to clot -- can be affected by significant changes in the level of omega-3s in the body. This includes making additions or reductions in the levels consumed regularly. While these omega-3 fats are essential nutrients for all of us, there is a need to be aware of potential interactions with medicines affected by blood’s tendency to clot.

One such concern is the condition you mention, deep vein thrombosis, in which blood flow is restricted in a vein because a clot has formed. (Read more about DVT at b.link/dvt2020.) One therapy for DVT involves anticoagulants, also referred to as blood thinners -- including the one you take, Coumadin (brand name for warfarin). Such therapies are utilized to fine-tune coagulation to prevent unwanted blood clots, while maintaining the ability to form clots where needed.

When using anticoagulant medications, it is essential to test -- both initially and periodically -- to establish and adjust the dose needed. Once the dose is determined, you don’t want to make changes by adding or stopping elements that can ruin the recipe.

You mentioned that you cook; consider taking a look at a cookbook that focuses on this issue. I am familiar with two such books, both written by physicians: “The Coumadin Cookbook” by Rene Desmarais and “The Dr. Gourmet Diet for Coumadin Users” by Timothy Harlan.

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.