Winter 2008

Dietary Herbs and Supplements
By Becky Dorner, RD, LD
Aging Well
Vol. 1 No. 1

“My daily multivitamin helps to keep my energy level up.”

“St. John’s Wort helped cure my depression.”

If you’ve heard similar statements from clients, you’re not alone. The National Health and Nutrition Examination Survey indicates that at least 50% of American adults regularly take vitamins and minerals and/or herbal and other supplements. And that includes older adults.

The Framingham Heart and Offspring Studies reported that 59% of women and 43% of men aged 67 to 96 took dietary supplements, and of those, 10% to 14% included herbs. Many take them because they feel their diets aren’t sufficient. This is more likely to be the case for those unable to shop for and prepare food on their own.

Are They Safe?
A common misperception is that all supplements are safe. There are approximately 30,000 available on the U.S. market, many of which have not undergone testing to ensure security and effectiveness. With few manufacturing standards in place, products may be inconsistent in their level of active ingredients, and the potential for contamination is a real concern. There’s also inadequate evidence for the safety of many supplements elders hope will help with ailments (ginkgo biloba for memory, glucosamine for joint health, etc.). Other concerns include the possibility of older adults spending more on supplements than food, that supplements may interact poorly with over-the-counter (OTC) or prescribed medications, and that supplements may have other harmful effects, including physiological changes affecting their absorption and metabolism.

With so many herbs and supplements on the market, all cannot be discussed, but here are some of the most commonly used among elders.

Positive Health Effects
There are some possible benefits of supplements for older adults. A few examples include the following:

• Vitamin D may help older adults who cannot get sufficient sunlight to absorb calcium, which helps reduce bone loss.

• Vitamin B12 may be needed for those aged 50-plus who don’t readily absorb it from food.

• Vitamins and antioxidants may reduce the progression of macular degeneration.

• Omega-3 fatty acids can reduce cardiovascular disease (CVD) risk by decreasing the risk of arrhythmia and lowering triglyceride levels, arterial plaque growth rates, and blood pressure. The American Heart Association (AHA) recommends eating fatty fish at least twice per week. Albacore tuna, salmon, lake trout, mackerel, herring, and sardines are high in the eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) types of omega-3 fatty acids.

• Tofu and other forms of soybeans, rapeseed (canola), walnut, flaxseed and their oils contain alpha-linolenic acid, which can become omega-3 fatty acid in the body.

• Patients with coronary heart disease should consume roughly 1 gram of EPA and DHA daily, preferably in the form of fish.

Patients should talk to their physicians if the capsule form is preferred. Doses higher than 3 grams of omega-3 fatty acids from capsules should be avoided unless recommended by a doctor, as they may cause excessive bleeding. It’s also important to find high-quality supplements, free of contaminants.

Questionable Benefit
There are many supplements of questionable benefit, too. Consider the following:
• Antioxidant vitamins E, C, and beta-carotene have potential health-promoting properties and may reduce CVD risk. A daily diet of nutrient-rich foods low in saturated/trans fat and cholesterol provides natural sources of antioxidant vitamins, minerals, and fiber. However, research indicates that antioxidants have little if any impact on improving cognitive function.

• It has not yet been determined whether high homocysteine levels in the blood are a major risk factor for CVD. Folic acid and other B vitamins help break down homocysteine in the body. But due to a lack of scientific evidence, the AHA does not recommend widespread use of folic acid and B vitamins. The recommended daily value for folic acid is 400 micrograms. Sources include citrus fruits, tomatoes, vegetables, and whole grains. Wheat flour is fortified with folic acid and can add approximately 100 micrograms per day to the diet. Supplements should be used only when diet doesn’t provide enough.

• Antioxidants, folate, B vitamins, along with a cholesterol-lowering diet, and medication may have a positive impact on cognitive function.

• The evidence on the impact of ginkgo biloba on cognitive function is inconclusive. One study indicated no improvement and another indicated little improvement in dementia patients. Ginko biloba is also a blood thinner and caution must be used when taking aspirin, vitamin E, or other anticoagulants.

• Glucosamine plus chondroitin sulfate: A 2006 study funded by the National Institutes of Health indicated that significant relief from osteoarthritis pain was not achieved among all participants using this combination but only among a small subgroup.

Possibly Harmful Supplements
Almost any nutrient can be potentially toxic if taken in large quantities over a long time. This is the case with fat-soluble vitamins, especially A and D. Dosages of vitamin A higher than 15,000 international units per day must be taken under medical supervision. Toxicity symptoms may include nausea, dizziness, skin changes, itchiness, irritability, vomiting, and headaches, and long-term use can cause hair loss, bone/muscle pain, liver damage, and an increase in blood lipid concentrations.

Too much vitamin D can create an overelevated calcium level, loss of appetite, increased thirst, nausea, vomiting, drowsiness, and abdominal pain. A long-term effect is the deposit of calcium in soft tissues such as blood-vessels or kidneys, where it can cause serious damage.

St. John’s Wort has been used for centuries to treat mental disorders and nerve pain. There’s limited evidence that it’s useful for treating mild to moderate depression. Side effects include sensitivity to sunlight, anxiety, dry mouth, dizziness, gastrointestinal symptoms, fatigue, headache, and sexual dysfunction. It interacts with some drugs by speeding up or slowing down their breakdown and may have harmful interactions with antidepressants, blood thinners, heart medications, and dextromethorphan. Anyone taking it should avoid tyramine-containing foods such as aged cheese, cured/aged meats, and wines. If depression is suspected, contact the patient’s doctor.

Basically, clients should talk to their doctor before taking any supplement or OTC drug, especially if they have a chronic medical condition, are having surgery, or are taking prescription medications. Herbs can act the same way as drugs in the body and can interact negatively with other OTC or prescription drugs. If there are any concern-causing side effects, again, see a doctor.

Supplements can indeed be beneficial to older adults. It simply pays to do some homework.

— Becky Dorner, RD, LD is founder/president of Becky Dorner & Associates Inc., a dietetic education/information firm, and Nutrition Consulting Services Inc., a dietetic consulting firm, both based in Akron, OH. Her Web site is www.BeckyDorner.com.