A recent study indicates that for long-term heart protection, daily low-dose Vitamin D supplements may outperform a high once-monthly dosage. The research suggests potential heart-protective benefits associated with this supplement, particularly among older adults who are already using heart medications.
In a significant new study featured in The BMJ, it has been revealed that high-dose vitamin D supplements taken on a monthly basis may reduce the risk of heart attack and other major cardiac events in individuals aged 60 and above. While the degree of risk reduction observed was modest, the findings indicate that vitamin D supplementation may decrease the occurrence of heart attacks and the necessity for coronary revascularization procedures, which aim to restore blood flow to areas of the heart deprived of sufficient blood supply.
Vitamin D – Does it Have Heart-Protective Benefits?
To date, the research concerning the cardiovascular advantages of vitamin D has yielded conflicting results. Some prior studies have suggested that supplementation may not be effective in averting heart-related issues.
A comprehensive analysis, published in 2019 in JAMA Cardiology, encompassing 21 clinical trials and involving over 83,000 participants, concluded that vitamin D supplements do not lower the likelihood of experiencing a heart attack or stroke or reducing mortality associated with these events.
“These [latest] findings suggest that conclusions that vitamin D supplementation does not alter the risk of cardiovascular disease are premature,” Rachel Neale, PhD, and her study co-authors had written. She is the deputy coordinator of the population health department at the QIMR Berghofer Medical Research Institute in Queensland, Australia.
“These findings could prompt further evaluation of the role of vitamin D supplementation, particularly in people taking drugs for prevention or treatment of cardiovascular disease,” they added.
Large Trial Saw Heart Vitamin D Benefits
The analysis involved over 21,000 individuals aged 60 to 84 who were separated into two categories: one group received a monthly dose of 60,000 IU (international units) of vitamin D, while the other group received a placebo.
Participants with a history of daily vitamin D intake exceeding 500 IU, as well as those with a medical history including high calcium levels, hyperparathyroidism, kidney stones, soft bones osteomalacia, and sarcoidosis (a condition characterized by the growth of small collections of inflammatory cells), were excluded from the study.
On average, the treatment spanned a period of five years, with more than 80 percent of the participants reporting compliance by taking at least 80 percent of the prescribed study tablets.
Throughout the trial, 1,336 participants experienced significant cardiovascular issues, with a rate of 6.6 percent in the placebo group compared to 6 percent in the vitamin D group.
While the difference in cardiovascular event rates between the two groups was relatively modest, individuals taking vitamin D exhibited a 9 percent lower rate of major cardiovascular events compared to those receiving a placebo, equivalent to a reduction of 5.8 events per 1,000 participants.
Specifically, the rate of heart attacks was 19 percent lower, and the rate of coronary revascularization was 11 percent lower among the participants in the vitamin D group. However, there was no discernible difference in the incidence of strokes between the two groups.
“Overall, the effect of the dose given to this population was small,” Anastassios G. Pittas, MD, said. He is the chief of the division of endocrinology at Tufts Medical Center in Boston. “But then if you consider the low costs [20 cents per tablet or less] and overall safety, and you apply this at the large public health level, it may have important implications.”
Dr. Pittas highlights that in the current study, vitamin D was associated with preventing 6 out of 1,000 cardiovascular events. However, it’s worth noting that typically, a minimum significant reduction threshold is set at 20 to 30 fewer events per 1,000.
In a subgroup analysis, the researchers observed a potential stronger impact in individuals who were initially using statins or other cardiovascular medications.
Although the researchers emphasized that these findings did not reach statistical significance, Dr. Pittas found the effect in this particular population to be intriguing.
“People who take statins and cardiovascular drugs are at higher risk for developing cardiovascular disease,” he added.” I think you might argue that people who are at risk may benefit the most from the intervention.”
Why Was Such High Dose of Vitamin D Necessary?
The dosage of 60,000 IU utilized in this research is deemed elevated, as per Mayo Clinic’s guidance indicating a recommended daily intake for older adults ranging between 600 and 800 IU (or up to 24,000 IU monthly).
The decision to administer the dose on a monthly basis was made by the investigators to enhance adherence. Shifting from a daily regimen to a monthly one may potentially enhance compliance.
Additionally, the researchers aimed to assess the outcomes when individuals exceed the recommended range for vitamin D intake.
“When we’re trying to prevent a specific condition such as cardiovascular disease or diabetes, then we may need to give more than the typical dose of vitamin D,” Pittas said. “In general, however, it is believed that it is better to take vitamin D daily than nondaily, as constant exposure to moderate doses is thought to be more physiologic than intermittent exposure to high doses.”
However, excess of a beneficial substance can have harmful consequences. Mayo Clinic reports that prolonged daily intake of 60,000 IU of vitamin D has been demonstrated to lead to toxicity.
In conclusion, Pittas emphasizes that it would be premature to make broad inferences about vitamin D’s effects on the general population based solely on this single study. The balance between the benefits and risks of vitamin D varies depending on the specific target population, their medical status, and the differentiation between “treatment” and “supplementation,” as outlined by Pittas.
Signs of Vitamin D Deficiency
While some individuals can obtain an adequate amount of vitamin D from natural sources, such as specific foods as stated by the Harvard T.H. Chan School of Public Health, and sunlight as mentioned by UCLA Health, it is estimated by the National Institutes of Health that approximately 25% of adults in the United States do not receive sufficient vitamin D.
The University of Nebraska-Lincoln has compiled the following symptoms as potential indicators of a vitamin D deficiency and strongly recommends that individuals experiencing these symptoms consult their healthcare provider:
- Persistent fatigue
- Difficulty sleeping
- Bone pain or discomfort
- Feelings of depression or sadness
- Hair loss
- Muscle weakness
- Decreased appetite
- Increased susceptibility to illness
- Pale complexion
Recommended For You
