The sunshine vitamin
This vitamin, as you may have guessed, is vitamin D. Whimsically known as the sunshine vitamin, vitamin D has several very serious important functions like maintaining your bone structure and calcium reserves, yet its role in the body is so far reaching that a vitamin D deficiency can affect you neurologically, as well as physically. A vitamin D deficiency can literally devastate your health.
Role of vitamin D in health
Unlike other vitamins, vitamin D is unique in that it acts more like a hormone than a vitamin. Like other hormones in your body, vitamin D plays a part in managing your mood. If you have vitamin D deficiency, you will be more prone to depression and anxiety, whilst people with adequate vitamin D levels are better able to manage their mood and the occasional hardships of life.
Vitamin D maintains calcium levels in your blood and bone by managing the absorption of minerals from the intestines . When your calcium levels aren't managed appropriately, you will feel fatigued and weakened. Over time, this malaise becomes more and more severe, crippling you both mentally and physically. Not only do you not have the energy or willpower to live your life, your body itself begins to break down as bones soften, muscles weaken, and the parathyroid gland works overtime to try and maintain calcium levels, leaching it away from your bones.
Left untreated for a long period of time, a condition called osteomalacia results. Like osteoporosis, the bones are weakened by vitamin D deficiency, but may even become deformed as the condition progresses. Bowed legs and difficulty walking are the most dramatic effect of this deformation, mostly occurring in children, where the condition is called rickets. In adults, the pelvis can become deformed, and the spine may even bend out of shape as it weakens. This has a startling effect on mobility and needs to be addressed promptly to prevent the disease from progressing any further.
Vitamin D weight loss
Vitamin D benefits weight loss to some degree when combined with ample amounts of calcium from dairy. In recent studies, it has been shown that vitamin D and calcium levels influence how much weight you will lose when dieting, and if you have a vitamin D deficiency or don't consume enough calcium, this could be slowing down your dieting efforts.
According to the study, participants saw an increased chance of attaining a higher weight loss after 6 months than those who consumed minimal vitamin D and calcium. The effects of vitamin D on weight aren't so clear cut as of yet, but evidence is mounting towards a supportive effect towards maintaining a healthier weight when your vitamin D levels are in check.
Vitamin D and depression
Vitamin D plays a part in managing depression, and a vitamin D deficiency is thought to be one of the most important factors contributing towards seasonal affective disorder. This condition affects sufferers during the colder, darker months when people are more prone to staying inside away from bad weather and the cold temperatures.
Those who suffer from seasonal affective disorder find themselves depressed and don't understand why they feel so below normal and this is potentially exacerbated by lack of sun exposure and falling vitamin D levels. As such, seasonal affective disorder may even be a symptom of vitamin D deficiency. When vitamin D is supplemented, depression begins to disappear and the condition largely resolves itself.
There is also evidence to suggest that adequate vitamin D intake is a good way to prevent other forms of depression including minor depressive disorder and major depressive disorder. In this study, it was found that people who suffer from either of these forms of depression were 14 percent more likely to have a vitamin D deficiency.
Vitamin D and cancer
Vitamin D has anti-tumor properties and can reduce your chances of acquiring many different kinds of cancer. In particular, studies have found that men who are exposed to less of the sun's ultraviolet radiation, and thus having lower vitamin D levels, are more susceptible to prostrate cancer.
Colon cancer is also largely dependent on vitamin D levels and adequate vitamin D can decrease your risk of colon cancer 3 fold. The risk of all cancers is decreased when both vitamin D and calcium levels are kept in the normal range, and vitamin D deficiency may actually be a risk factor for cancer.
Now this needs to be taken with a grain of salt. Whilst there are clear cancer reductions noted through a large quantity of studies, there is no evidence that taking more vitamin D than your body needs will offer any further reduction in cancer risk. What the studies are saying is that vitamin D deficiency places you at a much higher risk for cancer compared to those who have optimal vitamin D levels.
If cancer runs in the family or you'd just like to reduce your risk in any way that you can, it's a great idea to have a doctor check your vitamin D levels. If you have a deficiency you can reduce cancer risk with vitamin D supplements. Otherwise, if your levels are in the normal range, vitamin D supplements may not offer any benefits above what you're already getting.
Osteoporosis and osteomalacia
Osteporosis and osteomalacia are two more chronic diseases that mostly affect older people. In the case of osteomalacia, this condition is usually due to vitamin D deficiency or a thyroid hormone imbalance (Parathyroid hormone is influenced by vitamin D levels). Osteoporosis, on the other hand, tends to increase in prevalence as you get older.
Both of these conditions lead to structural deformities and weak bones, and it is important to reduce your risk if you want to enjoy your mobility well into middle-age and retirement. Osteomalacia prevention merely involves maintaining adequate vitamin D levels. If your vitamin D levels are in check, and your thyroid gland is working properly, you are generally safe from this condition.
Osteoporosis is not so easy to avoid, and will creep up on you as you age. The easiest way to slow down the onset of osteoporosis and reduce your risk of suffering from the harsher symptoms is to ensure you have an adequate vitamin D intake, as well as consume plenty of calcium, phosphorous, and magnesium. All these minerals are used to build and maintain your bone, and a deficiency of any of them will speed up the onset of osteoporosis. What's worse is that osteoporosis can not often be reversed to any great degree, even with medication, so you need to be getting the right nutrients every day to prevent it.
Why are so many people deficient in vitamin D?
Nutritionists aren't entirely sure why vitamin D deficiency is so widespread in societies where it shouldn't even exist anymore. The causes could range from increased reliance on junk food that is devoid of nutrients, to a simple avoidance of the sun now that we are aware of the risk of skin cancers from ultraviolet light.
Food has never been a major source of vitamin D for humans, with most foods only containing small amounts of the vitamin, and nowhere near the amount the body really requires to function at its best. Dairy and seafood generally contains the most vitamin D of any food, yet as vitamin D is fat soluble, the shift towards low fat and skim dairy products means that less vitamin D remains in the food.
The sun however, has always been our major source of vitamin D. When exposed to ultraviolet light, the UV rays ionise cholesterol in the skin and help the body produce vitamin D. These same UV rays that produce vitamin D are the source of cancers, photo-aging, and general damage to the skin. Now that we know about these negative effects of sunlight, more people are using sun blocks, wearing protective clothing, and avoiding exposure to the sun when UV rays are most intense. These precautions are absolutely great for our skin and health in general, but lead to vitamin D deficiency. It's a genuine double-edged sword.
Vitamin D deficiency symptoms
If you think you might have a vitamin D deficiency, the symptoms to look out for include:
- Cognitive impairment - brain fog
- Tiredness and lethargy
- Muscle pain / muscle cramping
- Joint pain
- Back pain
- Weakened immune system
- Depression / anxiety
If you don't get out in the sun much, or eat much salmon or other oily fish, and you are experiencing a few of these symptoms, there's a good chance that you are in fact vitamin D deficient. Lower back pain, as well as joint pain in your hips and legs are the most common symptom of vitamin D deficiency and if you aren't getting any sunlight or eating seafood, a trip to the doctor should be committed to your 'to-do-list'. It may be the best thing you ever do.
Vitamin D RDA
The RDA of vitamin D is 600 IU per day for adults. In order to understand why vitamin D deficiency is so prevalent, you only need to look at the vitamin D content of foods. Eggs, for example, are considered high in vitamin D compared to the majority of foods, yet an egg only contains 41 IU of vitamin D. This is found in the yolk too, so those who only use the egg whites will not consume vitamin D from the eggs they eat. Add a lack of sun exposure and it's clear why so many people are deficient in vitamin D.
On top of this, although the RDA of vitamin D is only 600 IU, many studies call for this amount to be increased, stating that it is not enough. 600 IU is merely the recommended lower limit of intake where deficiency is sure to occur below this consumption level.
Vitamin D side effects
Unless you're consuming too much, vitamin D has no side effects. This is because it is a necessary nutrient that the body requires to work properly. Consuming the right amount will always benefit your body without causing problems. Like all fat soluble vitamins though, vitamin D overdose can occur with dosage that isn't sensible.
Daily dosages of up to 3000 - 4000 IU of vitamin D are considered to be the upper tolerable limit for adult consumption. If you don't have a deficiency and are just seeking to maintain your levels, any more than this is likely to cause you problems. If you do have a vitamin D deficiency however, your doctor will generally prescribe a very high daily or weekly dosage of the vitamin, and this isn't harmful either, because your blood levels of the active 25-hydroxyvitamin D will be far below normal. A large dosage is required in this case to boost these levels up, and your doctor will switch you to a maintenance dosage once your levels are in the beneficial range.
If you do consume too much vitamin D, it can take anywhere from weeks to months before side effects start to occur. This is because vitamin D gradually accumulates in fat. If you're considering taking vitamin D, it is always best to consult your doctor and actually have your vitamin D levels checked first to avoid problems from occurring further down the track. Knowing your blood levels takes away all the transparency in dosage and allows you to take a safe amount that will benefit your health.
For reference, the side effects of an overdose include:
- Nausea and vomiting
- Dehydration and excessive thirst
- Muscle weakness
Most of these side effects are caused by the hypercalcemia that is provoked by excess vitamin D. This is a condition where there is too much calcium in the blood and can be dangerous if left untreated. Essentially, just as vitamin D allows your body to absorb calcium from the food you eat and use the mineral to make healthy bone, too much vitamin D increases this action to the point that there is too much calcium in your blood and this is what causes the main side effects of vitamin D.
Foods high in vitamin D
Some of the other foods high in vitamin D include:
- Cod liver oil - 1300 IU approx per tablespoon
- Swordfish - 500 IU approx per 3 ounces
- Tuna - 150 IU approx per 3 ounces
- Eggs - 40 IU approx per 1 egg yolk
You'll also find that milk and margarine spreads are sometimes fortified with vitamin D to increase their nutritional value. This is all well and good, but they still don't provide much vitamin D per serving size, and it would be unrealistic to rely on fortified foods to reach the lofty goal of at least 600 IU of vitamin D.
Vitamin D supplements
If you don't get much sunlight or eat salmon on a daily basis, you are certainly benefiting your body by taking vitamin D supplements. These supplements contain the same form of the vitamin that your skin produces in response to sunlight, so the form of vitamin D isn't an artificial analogue. One 1000 IU capsule can be taken every day to ensure you don't run into problems with vitamin D deficiency.
For pre-existing deficiencies, or a deficiency diagnosed by a doctor however, you will often be best taken much more than this to correct the problem much more quickly. It is not uncommon for a doctor to prescribe 15000 IU of vitamin D or more to be taken on a daily basis for months to correct a deficiency, and even after your levels reach a normal range, you will be urged to take at least 3000 IU a day to maintain these levels.
This is why you absolutely must see your doctor should you have any concern that your vitamin D levels are low. It can take months of taking large amounts like this to reach a healthy range, and if you leave the problem by itself and just take a nutritional dosage, you will remain deficient instead of getting better.
As with all health conditions, you doctor is there to help you, as well as to provide tests that can accurately diagnose you and take away the guesswork. A trip to the doctor today means better health well into the future.