The Top Five Dietary Supplements Among American Seniors: Do They Have a Role in Hospice Care?

Dietary supplements are big business in the USA. Three out of four Americans aged 60 or older take at least one supplement. These supplements are often continued in hospice care despite limited evidence of benefit. While serious complications of supplement use are uncommon, side effects and drug interactions can be uncomfortable or even dangerous. It is essential for hospice clinicians and pharmacists to be aware of any products patients may be taking and be on the lookout for complications.

With thousands of products in the marketplace containing vitamins, minerals, botanicals, amino acids, probiotics and so on, no clinician can know them all. However, the top five most common supplements among American seniors are a good start:

  1. Multivitamin/mineral
  2. Vitamin D
  3. Omega-3 fatty acids
  4. Calcium
  5. Vitamin B12


Studying multivitamin effects is complicated by the diverse formulations on the market, which can include over 50 active ingredients. However, many users report nausea and other digestive issues. Products containing iron can be especially problematic, reducing absorption of many antibiotics and drugs that treat Parkinson’s disease. Additionally, individuals taking multivitamins may be at risk of excessive intake of some nutrients, especially if they consume them in food, other supplements, or nutrition drinks. The downsides of multivitamins combined with little to no evidence of benefit make a strong case against their use in hospice care.

Vitamin D

Vitamin D is one of the few supplements regularly recommended by doctors. It is especially important for those at risk of osteoporosis due to its role in calcium absorption, but excessive consumption can lead to complications for the heart and kidneys. Because vitamin D deficiency has been associated with muscle weakness, fatigue and depression, supplementation may have benefits in end-of-life care when deficiency is confirmed or suspected. There is also evidence supporting its use in pain management for cancer patients.

Omega-3 Fatty Acids

Omega-3s are fats found in seafood and other dietary sources. Supplements are typically oil derived from fish or krill. Despite many correlations between health and seafood intake, studies have not found much if any benefit from omega-3 supplements. The strongest indication for omega-3 supplements is to reduce symptoms of rheumatoid arthritis. Although risk of drug interactions is low, there is some concern that omega-3 supplements can increase the effect of anticoagulant and blood pressure medications. They can also cause unpleasant tasting burps, bad-smelling sweat, and gastrointestinal symptoms such as heartburn, nausea, and diarrhea.


Calcium is often indicated alongside vitamin D for individuals at risk of osteoporosis, but this is not a concern in end-of-life care. However, in rare cases low calcium levels can cause symptoms such as muscle cramps, confusion and depression. Vitamin D alone is sometimes used for hypocalcemia from specific disorders such as hypoparathyroidism. It is relatively difficult to take too much calcium due to the size of the tablets, although overuse of calcium antacids has been implicated in some cases. Intake over 2,000 mg per day raises the risk. Additionally, calcium supplements at normal doses may cause constipation, gas and bloating.

Vitamin B12

B12 deficiency is common among older adults. It can also be caused by restrictive vegetarian diets, excessive alcohol consumption, malabsorption disorders, and drugs such as metformin and proton pump inhibitors (e.g., omeprazole, pantoprazole). Symptoms of low B12 include fatigue, anxiety and depression, so supplementation with B12 may have a place in end-of-life care if deficiency is confirmed or suspected. Sublingual and intranasal formulations are widely available, as are vitamin B12 injections. Even very high oral doses of B12 are well tolerated since, as a water-soluble vitamin, excess amounts are excreted in urine.

Discontinuing Supplements in Hospice

While some of the supplements discussed above may have narrow applications for symptom management, most patients are unlikely to benefit from them. This plays into larger deprescribing conversations with patients and caregivers. Some patients may be resistant to discontinuing supplements, especially if they have been taking them for a long time on advice from a medical provider. In most cases continuing these supplements is unlikely to cause harm, but it may be worth pointing out that omega-3s, multivitamins and calcium present a significant pill burden and swallowing challenges due to their size and may also contribute to gastrointestinal distress. Apart from omega-3s’ application for rheumatoid arthritis, they are also all typically taken for long-term health rather than short-term benefit.

In contrast, vitamins D and B12 may have symptom-management potential in some cases. They are also well-tolerated and widely available in highly concentrated liquid forms. This makes them better candidates for continuing if medically appropriate and in accordance with a patient’s wishes.

Further Reading

Enclara’s Palliative Pearls series features in-depth clinical case studies and reviews. The following include information related to this topic: