DEAR DR. BLONZ: I appreciate that you answer questions about health claims made on social media. I am continually amazed when I want to learn about a condition and then find it can be treated successfully using a particular promoted product. It seems there are cures out there for everything, often promoted by doctors, but it is unclear whether these are doctors with genuine credentials. What bothers me is the lack of guardrails, and I wanted your comment on how all this continues to exist. -- S.K., Lombard, Illinois

DEAR S.K.: I am less concerned with who hawks the products, and more so with the products themselves. A laissez-faire attitude over the past few decades has spawned an unbridled atmosphere of health claims associated with nutritional supplements. Social media, often with an anti-science bent, has amplified the situation. While it is against the law to make unsubstantiated health claims, the Food and Drug Administration (FDA), Federal Trade Commission (FTC) and other consumer protection agencies don't have the resources to make any significant dent in the infractions.

Another element of uncertainty involves adding supplements alongside a doctor-prescribed medication regime. A 2017 study in the respected journal American Family Physician reported that nearly 25 percent of U.S. adults take supplements along with their prescription medications -- and possible interactions must be considered. (For more on drugs, supplements and potential interactions, see b.link/cvkx2c3.)

While consumer protection laws can vary between states, scientific literature has no such boundaries. The FDA, FTC, state agencies and other respected elements of the supplement industry wouldn't dispute the need for a mechanism to regulate claims that lack clinical evidence, but testing for safety and effectiveness can be a thorny issue. Manufacturers might have a lack of economic incentive to fund research if it involves non-proprietary substances -- because other companies selling the same substances could benefit from their results when published. Many companies offer "proprietary blends," but the missing link is clinical evidence showing that their product's blend works as they claim. Then there is the issue of bogus claims that escape any accountability. The burden of proof should rest with the companies profiting from supplement sales -- not consumer protection agencies inadequately funded for the task.

I would support a goal for the supplement industry to establish a self-policing policy to evaluate their health claims. A panel of independent scientists could be empowered to decide on the essential proof for any particular claim. A ratings system as simple as the red-yellow-green of a traffic light could link to a consumer-friendly database of evidence.

Having something like this on the product's label or website could empower consumers to patronize brands that favor consumer protection and education. In the meantime, I will continue to respond to my readers' queries.

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 on Medicare and had a bone scan as a part of my annual wellness checkup, which showed that I have weak bones in the form of osteopenia in my hips and spine, but other areas were in the normal range. I was told to increase my calcium and vitamin D intake, which I am doing; in addition, I was given a list of exercises to help keep my bones strong. This test result came as a surprise, as I have no pain and have never had a broken bone. I will add the bone-strengthening exercises to my routine.

I also have high blood pressure that is being successfully treated with a calcium channel blocker medication. Is there any interaction between taking a calcium channel blocker and taking calcium as a dietary supplement I should be aware of? Neither my doctor nor pharmacist mentioned any such possibility. -- W.P., Raleigh, North Carolina

DEAR W.P.: I commend you and your physician for including a bone scan in your wellness checkup. We shouldn't wait until we're eligible for Medicare to get our bone strength tested. (Those on Medicare are entitled to a yearly wellness visit as part of their healthcare. For more on this, see b.link/aqdrzczc.)

The fact that you had no idea there were issues with your bone strength underscores the importance of undergoing such testing -- the sooner you diagnose and treat bone-strength issues, the greater the odds it can be stopped or even reversed. I understand your need to learn more, given that calcium is involved in both of your health situations, and you want both medications to function as intended.

Calcium channel blockers can be prescribed for hypertension (high blood pressure) because they prevent the contraction of certain smooth muscles surrounding the blood vessels. For the muscle around the vessel to contract, a small amount of calcium has to pass through a channel in the membrane (outer skin) of the muscle. Calcium channel blockers are so named because they slow the movement of calcium through these channels, thereby keeping the blood vessels relaxed. (For more on calcium channel blockers, see b.link/r5jfpw3.)

There is little connection between the calcium present in your system via your diet or your supplement and the ability of a calcium channel blocker to do its job. It should be interesting for you to track your bone strength in future testing. (Read more about bone-strengthening exercises at b.link/jgisklr.)

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 a female in my early 20s and have started taking a mineral supplement to build up calcium before I start losing it. I was wondering if there is a best time of day to take this? -- K.W., Nashville

DEAR K.W.: I applaud your strategy of working on your bones while your bone-building window is open. As a general rule, taking a calcium supplement with or after your biggest meal is best. Avoid taking more than 500 mg at a time.

Some people get their calcium from calcium-fortified beverages, such as orange juice. Recommendations regarding side effects and safety when taking calcium can be found at b.link/jffcvd5m.

Exercise and an active lifestyle play a big role in building bones -- activity tells your body that the bones are needed for work, and the body responds by building them up and keeping them strong.

DEAR DR. BLONZ: Do you have any information about the value of drinking oxygenated water, in which oxygen is infused into special water to facilitate health for those with cardiovascular disease? Could you refer me to the straight scoop? -- M.A., Hayward, California

DEAR M.A.: It's easy to burst this bubble: Our bodies are set up to get oxygen through breathing, not swallowing.

Like most gases, oxygen is poorly soluble in water, so there won't be much oxygen in a serving of oxygenated water. Consider carbonation, where carbon dioxide gas (CO2) gets dissolved in water. Generally, gas becomes more soluble in water with lower temperatures and higher pressures. Carbonation occurs when CO2 is forced into very cold water under high pressure. The container is securely sealed when the desired amount of gas has been added. This liquid looks like plain liquid in the sealed container as it sits, but CO2 bubbles will form and escape when you open the container, which relieves the pressure. Bubbles also form if the liquid warms in an open glass or when it is moved, shaken or stirred -- which increases the kinetic energy (heat), further decreasing gas solubility.

When consumed, the tiny amount of oxygen still present after the loss when the container was opened drops even further as the liquid rises to body temperature. You will experience a telltale belch as it continues warming while it travels toward your stomach. There is no basis to expect that the minuscule amount ending up in your digestive system will impact the level of oxygen delivered to your muscles or brain via the bloodstream.

Drinking oxygenated water remains an unproven concept. Misleading marketing can entice the vulnerable through the door, but there is no evidence that you get anything more than expensive water, a burp, and more containers to recycle.

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.