Over the past decade, researchers have come up with a vast amount of factual evidence that vitamin D is extremely important to maintaining health and preventing and even treating multiple physical and mental health problems. For example, studies have shown that too little vitamin D may trigger breast cancer, rheumatoid arthritis, brittle bones, heart attacks and more.
Recently, scientists have discovered two more extraordinary benefits to getting enough vitamin D through sun exposure and supplements. It turns out a lack of the remarkable vitamin could result in sports-related muscle injuries. And what is the most remarkable for subject of this post, vitamin D may help reduce amount and decrease in size amyloid plaques in the brain associated with Alzheimer's disease.
University of Cambridge and University of Michigan Study, 2009
Researchers from the Peninsula Medical School, the University of Cambridge and the University of Michigan, have for the first time identified a relationship between Vitamin D, the "sunshine vitamin", and cognitive impairment in a large-scale study of older people. The importance of these findings lies in the connection between cognitive function and dementia: people who have impaired cognitive function are more likely to develop dementia.
The study was based on data on almost 2000 adults aged 65 and over who participated in the Health Survey for England in 2000 and whose levels of cognitive function were assessed. The study found that as levels of Vitamin D went down, levels of cognitive impairment went up. Compared to those with optimum levels of Vitamin D, those with the lowest levels were more than twice as likely to be cognitively impaired.
In humans, Vitamin D comes from three main sources – exposure to sunlight, foods such as oily fish, and foods that are fortified with vitamin D (such as milk, cereals, and soya drinks). One problem faced by older people is that the capacity of the skin to absorb Vitamin D from sunlight decreases as the body ages, so they are more reliant on obtaining Vitamin D from other sources.
Dr. Iain Lang from the Peninsula Medical School, who worked on the study, commented: "For those of us who live in countries where there are dark winters without much sunlight, like the UK, getting enough Vitamin D can be a real problem – particularly for older people, who absorb less Vitamin D from sunlight. One way to address this might be to provide older adults with Vitamin D supplements. This has been proposed in the past as a way of improving bone health in older people, but our results suggest it might also have other benefits. We need to investigate whether vitamin D supplementation is a cost-effective and low-risk way of reducing older people's risks of developing cognitive impairment and dementia."
UCLA and UC Riverside Study, 2009
UCLA scientists and colleagues from UC Riverside and the Human BioMolecular Research Institute have found that a form of vitamin D, together with a chemical found in turmeric spice called curcumin, may help stimulate the immune system to clear the brain of amyloid beta, which forms the plaques considered the hallmark of Alzheimer's disease.
The early research findings may lead to new approaches in preventing and treating Alzheimer's by utilizing the property of vitamin D3 - a form of vitamin D - both alone and together with natural or synthetic curcumin to boost the immune system in protecting the brain against amyloid beta.
Vitamin D3 is an essential nutrient for bone and immune system health; its main source is sunshine, and it is synthesized through the skin. Deficiencies may occur during winter months or in those who spend a lot of time indoors, such as Alzheimer's patients.
Using blood samples from nine Alzheimer's patients, one patient with mild cognitive impairment and three healthy control subjects, scientists isolated monocyte cells, which transform into macrophages that act as the immune system's clean-up crew, traveling through the brain and body and gobbling up waste products, including amyloid beta. Researchers incubated the macrophages with amyloid beta, vitamin D3 and natural or synthetic curcumin.
Tohoku University Study, 2011
In the new research, investigators tested the protective properties of vitamin D on unsuspecting lab mice, and determined that the chemical can work alongside transporter proteins in the blood-brain barrier for preventing the buildup of amyloid beta peptides in the human brain. This type of buildup is one of the most well-known hallmarks of the condition. Experts at the Tohoku University hypothesize that a lower chance of increased amyloid concentrations leads directly to a lower chance for a person to develop Alzheimer's.
The study takes a closer look at how amyloid beta is removed from the brain. It would appear that this process is dependent on amounts of vitamin D available for use, as well as on the alterations that age produces in BB transporter proteins. The latter are responsible for moving amyloid beta in and out of the brain. Previous investigations have already linked reduced concentrations of vitamin D to memory and cognition declines, especially in old age. As such, the new research builds up on past studies, taking them a step further.
Experimentally, the Japanese research team demonstrated that it's possible to increase the rate at which amyloid beta is removed from the brain by injecting the test mice with moderate amounts of vitamin D.
About Vitamin D
Vitamin D is a fat-soluble vitamin found in foods such as fortified dairy, cereals, eggs and fish oils. It plays an important role in the formation and maintenance of bones. It also regulates cell growth and immune function. The National Institutes of Health's Office of Dietary Supplements recommends 400 to 800 IU of the vitamin, depending on the age and overall health of health of the individual.
Vitamin D doesn't always get the attention it deserves, perhaps because very few foods in nature contain vitamin D. The best sources are salmon, tuna and mackerel (especially the flesh) and fish liver oils. Beef liver, cheese and egg yolks also contain small amounts.
Also, vitamin D is actually produced in your body when ultraviolet rays from sunlight strike your skin. The UV rays trigger synthesis of vitamin D, which then gets converted in your liver into its active form.
This means one of the best ways to get vitamin D is to spend about 10-15 minutes a day outside in the sun. Keep in mind that wearing sunscreen will prevent you from getting adequate vitamin D outdoors. In the summertime, an easy solution is skipping sunscreen on your legs for the first 15 minutes in the sun. Just make sure you apply in time to prevent any burns or damage. Your doctor may also recommend vitamin D supplements to treat a variety of conditions such as osteoporosis, cancer and diabetes.
Vitamin D supplements are generally safe to use, although increased amounts of the vitamin may lead to increased calcium levels in the body. This can cause confusion, disorientation, kidney damage, nausea, vomiting and poor appetite. The supplements may also interfere with certain blood pressure and corticosteroid medications.
Talk to a doctor before using vitamin D supplements to determine if they are right for you. You doctor may also suggest the appropriate dose depending on your age, pre-existing conditions and other medications you might be taking.
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