Medical Minutes
Know your vitamin D levels
For the holidays, give yourself a present. Make sure you get your vitamin D levels checked and if they are low, get treatment. A new study now shows that vitamin D levels in the blood are linked to cardiorespiratory fitness.
“Our study shows that higher levels of vitamin D are associated with better exercise capacity,” said Dr. Amr Marawan, who is an assistant professor of internal medicine at Virginia Commonwealth University in Virginia. “We also know from previous research that vitamin D has positive effects on the heart and bones. Make sure your vitamin D levels are normal to high. You can do this with diet, supplements and a sensible amount of sun exposure.”
It is well established that vitamin D is important for healthy bones, but there is increasing evidence that it plays a role in other areas of the body including the heart and muscles. Cardiorespiratory fitness, a reliable surrogate for physical fitness, is the ability of the heart and lungs to supply oxygen to the muscles during exercise. It is best measured as the maximal oxygen consumption during exercise, referred to as VO2 max. People with higher cardiorespiratory fitness are healthier and live longer.
This study investigated whether people with higher levels of vitamin D in the blood have improved cardiorespiratory fitness. The researchers looked at 1,995 participants (45 percent women, 49 percent white, 13 percent had high blood pressure, and 4 percent had diabetes). Participants in the top quartile of vitamin D had a 4.3-fold higher cardiorespiratory fitness than those in the bottom quartile. The link remained significant, with a 2.9-fold strength, after adjusting for factors that could influence the association such as age, sex, race, body mass index, smoking, hypertension and diabetes.
“The relationship between higher vitamin D levels and better exercise capacity holds in men and women, across the young and middle age groups, across ethnicities, regardless of body mass index or smoking status, and whether or not participants have hypertension or diabetes,” said Dr. Marawan.
Get a grip
As we age, we may develop certain disabilities that make it difficult to walk, climb, balance or maintain our fine motor skills. In turn, these changes can affect our ability to perform routine, daily tasks. However, experts say that it is often possible to treat these difficulties before they lead to disability.
To learn more about how and whether being strong can ward off disability, a team of researchers examined information from a study called SHARE. It involved a survey of people aged 50 and older across most European Union countries and Israel every two years. The survey collected information about health, social and economic status, and participants’ social and family networks. A total of 30,434 people participated in this survey.
The researchers examined the effects of grip strength and cognition (the ability to remember, think, and make decisions) and how those affected the participants over time. The researchers learned that maintaining grip strength and protecting mental ability might prevent or delay disability.
The researchers found that older adults who perform physical and mental training may be able to slow down their physical decline and potentially prevent future problems such as the loss of independence, reduced quality of life, the likelihood of developing depression and dementia, and even death.
How much protein do you consume a day?
Researchers are now investigating whether eating more protein may contribute to helping people maintain independence. Protein is known to slow the loss of muscle mass. Having enough muscle mass can help preserve the ability to perform daily activities and prevent disability. Older adults tend to have a lower protein intake than younger adults due to poorer health, reduced physical activity, and changes in the mouth and teeth.
To learn more about protein intake and disability in older adults, a research team used data from the Newcastle 85+ Study conducted in the United Kingdom (UK). The researchers approached all people turning 85 in 2006 in two cities in the UK for participation. At the beginning of the study in 2006 to 2007, there were 722 participants, 60 percent of whom were women. The participants provided researchers with information about what they ate every day, their body weight and height measurements, their overall health assessment and their medical records.
The researchers learned that more than one-quarter (28 percent) of the adults over age 85 had protein intakes below the recommended dietary allowance. The researchers noted that older adults who have more chronic health conditions may also have different protein requirements. To learn more about the health benefits of adequate protein intake in older adults, the researchers examined the impact of protein intake on the increase of disability over five years.
The researchers’ theory was that eating more protein would be associated with slower disability development in very old adults, depending on their muscle mass and muscle strength. As it turned out, they were correct. Participants who ate more protein at the beginning of the study were less likely to become disabled when compared to people who ate less protein.
John Schieszer is an award-winning national journalist and radio and podcast broadcaster of The Medical Minute. He can be reached at medicalminutes@gmail.com.