Use reliable literature sources for information about vitamins.

• Take magnesium with vitamin D3 for maximum absorption.
• Do not take magnesium with zinc or iron supplements. Wait a few hours to avoid poor absorption of zinc and iron.
• Take piperine with turmeric/curcumin to increase absorption.
• When taking calcium, also take vitamin D3 to increase absorption.
• Take pine bark extract containing L-arginine to prevent plaque buildup on artery walls and arteriosclerosis.

answer: The problem with health magazines is that the reliable information can be interspersed with not-so-reliable information. In some cases, hopeful claims are made based on experimental or animal data. In some cases, they may be clearly false, such as by mistake or because the advertiser is trying to sell supplements. In the example given above, vitamin D (D2 or D3) increases the absorption of calcium and magnesium, but this does not mean that they are necessary. Not recommended unless prescribed.

Piperine definitely increases the absorption of curcumin, the most active ingredient in turmeric. This increases both efficacy and toxicity. Zinc and iron compete for absorption and should not be taken at the same time. If it is deficient, it must be isolated. However, in clinical trials, neither pine bark nor L-arginine was found to be effective against coronary artery disease.

The first literature source I recommend is MedlinePlus.gov, maintained by the National Library of Medicine. It is also part of the National Institutes of Health. Most of the answers above are there. Some large institutions, such as Johns Hopkins University and the Mayo Clinic, have reliable information on many medical subjects.

Like your doctor, your local pharmacist can be a source of information, but some questions may require special expertise or the time and ability to research the answers.

Dear Dr. Roach: I read that the Centers for Disease Control and Prevention is now recommending additional COVID-19 vaccinations for seniors 65 and older. According to the article, the current version is very effective. I last received the Moderna vaccine in October 2023. Should I take it again? JLI

answer: The downside to another coronavirus vaccine is small for most people. The benefit is that it can provide increased protection against the coronavirus, especially the severe coronavirus that can put people in the hospital.

I will give another vaccine this spring to high-risk people, including those over 65 with additional risk factors such as diabetes, heart and lung disease, and those living in nursing homes. Highly recommended. The benefit for a 65-year-old who has been fully vaccinated and is otherwise healthy is small. Very old people (over 80s) will also benefit from booster vaccinations this spring, even if they are healthy.

Data is emerging that yearly vaccination against coronavirus disease (COVID-19) is effective. Although not yet proven, high-risk people may benefit from receiving the vaccine twice a year. In my opinion, people at very high risk, such as those mentioned above and people with immune system disorders, should receive the additional vaccine now.