Study under review: Effect of Vitamin D Supplementation on Pain: A Systematic Review and Meta-analysis.
Pain is a natural part of being human. It is so ingrained into our biology that we “just know” when we experience pain or when others experience pain. It is not uncommon to cringe or feel some pain ourselves when watching others be harmed. Pain is essentially a subjective perceptual experience that originates in sensory receptors throughout the body but is interpreted as pain by the conscious brain.
One possible way of classifying pain is in two groups: acute and chronic. We have all experienced acute pain – hitting our head, stubbing our toe, or worst of all, stepping barefoot on a Lego piece. These pain sensations vary greatly in strength and serve as a warning sign that continuing with an action may cause bodily harm or that something about the body isn’t as it should be. However, this pain subsides when the insult is removed or when the damaged area heals.
By contrast, chronic pain is defined by the International Association for the Study of Pain as “pain that has persisted beyond normal tissue healing time.” This timeframe is considered to be about three months, although some chronic pain disorders (such as rheumatoid arthritis) are characterized by short, recurrent “flares” of pain. Recent evidence has shown that chronic pain is associated with chemical, functional, and anatomical changes throughout the nervous system. These changes and the pain itself can also be brought about by tissue damage, inflammation, or injury to the nervous system.
Although vitamin D’s principal role in the body is to regulate bone health and calcium status, we now know that vitamin D plays a role in many biological processes. Vitamin D deficiency has been linked to various chronic pain conditions and vitamin D may influence the perception of pain through its effects on nerve conduction and health, inflammatory signaling, and immune activation.
A number of randomized controlled trials (RCTs) have investigated the effect of vitamin D supplementation on various types of pain, and several review articles have addressed these studies using qualitative (narrative) methods. This study performed a quantitative meta-analysis, to show what the full body of trial evidence shows for vitamin D supplementation and pain reduction.
Pain is something we are all familiar with, but some individuals suffer from disorders in which pain is chronic or recurring. Vitamin D has been implicated in many of these chronic pain conditions and numerous RCTs have investigated whether vitamin D supplementation can reduce pain in a variety of conditions. The current study was a meta-analysis of RCTs that sought to determine whether vitamin D supplementation can reduce pain compared to placebo.
Other Articles in Issue #24 (October 2016)
Interview: Josh Mitteldorf, PhD
Josh is well-known in the life-extension community, for looking deep into the literature and connecting the dots. We'll get his take on some interesting longevity-related topics. After 30 years wandering in the plasma physics of extragalactic radio sources, Mitteldorf came to the study of aging in 1996 to correct a fundamental error in the foundations of evolutionary theory. After 20 years, the revolution in biological concept of aging that he initiated is only now coming to fruition
When nitrate supplementation doesn’t involve supplements
We've covered several nitrate supplementation studies in previous ERDs. This trial is unique in that it studied the impact of a nitrate-rich diet on exercise performance.
Eat a day, skip a day?
Typical dieting can be a chore. An alternative is to eat less (or not at all) during certain time periods, otherwise known as fasting. This is the first trial to compare regular calorie restriction to alternate-day fasting.
The high cost of high heat cooking
The delicious browning and crusting of steak or chicken could also be harmful. This one-year long randomized trial looked at high-heat cooking versus gentler cooking, and its impact on insulin resistance.
Interview: Courtney Silverthorn, PhD
Are you in the life sciences, but not sure if you want to work in a lab? Courtney is uniquely qualified to give advice about this.
Does being insulin resistant affect weight loss on a low-fat or low-carb diet?
Weight loss is not a simple issue. The impact of a diet could be influenced by whether or not you’re insulin resistant, as examined by this one-year trial of a low-fat versus low-carb diet.
Examining the potential for edible sunscreen
Phytochemicals in plants are well known to have positive effects on chronic conditions, such as heart disease and cancer. But certain ones could also help you avoid ... sunburn.