Have you ever seen pictures of children with extremely bowed legs? It is a condition called rickets and it's from low levels of vitamin D, causing the bones to become soft and weak.
Vitamin D is crucial for bone health. It helps your body keep a good balance of calcium and phosphate in the blood. With low vitamin D levels, children can develop rickets and adults can develop osteomalacia, a condition in which weak bones cause bone pain, fractures, and muscle weakness.
Vitamin D also has many other functions in the body. It helps control the growth of your cells, improves your immunity, provides nerve and muscle strength, and reduces disease-causing inflammation in your body.
Some studies suggest it may help with type 2 diabetes, weight loss, multiple sclerosis, high blood pressure, depression, heart disease, colon cancer, and other types of cancer.
Nursing home residents seem to have significantly fewer falls when they start a daily vitamin D supplement.
While the jury is still out on all of the studies related to vitamin D, we know it is essential that you have enough but not too much so that it becomes harmful. Simply put, you need to have optimal levels of vitamin D.
How Do You Get Enough Vitamin D?
There are 3 ways for you to get vitamin D:
1. Your skin makes vitamin D through sunlight
2. You can get vitamin D from food
3. You can take a vitamin D supplement
Let's start with the sun on your skin.
As a general rule, exposure of the face, hands, arms, and legs to sunlight 2 to 3 times a week may produce enough vitamin D to stay healthy. Exposure should be about 1/4 of the amount of time it takes for you to get a mild sunburn. Depending on your skin color, this can mean from 5 to 30 minutes of sun exposure between 10 am and 3pm.
It is the ultraviolet B radiation in sunlight that helps your skin make vitamin D. Complete cloud cover reduces this radiation by about 50%. Shade, including the shade from severe pollution, reduces this ultraviolet B radiation about 60%.
How about food?
Surprisingly, there are not too many foods that are naturally high in vitamin D. The following list includes the highest foods in vitamin D:
Vitamin D Measured in IUs:
Cod liver oil, 1 tbsp, 1,360
Swordfish, cooked, 3 oz., 566
Sockeye Salmon, cooked 3, oz., 447
Mackerel, canned, 3 oz., 214
Sardines, canned, 3 oz., 197
Tuna Fish, canned in water, drained, 3 oz., 154
Orange juice Vitamin D-fortified, 1 cup, 137
Milk, Vitamin D-fortified, 1 cup, nonfat, reduced fat, & whole, 115-124
The abbreviation IU stands for "international unit" and is what you will find on food and supplement labels.
The third source of vitamin D is from supplements.
In general, there are two different forms of vitamin D on the market: ergocalciferol (also known as vitamin D2) and cholecalciferol (also known as D3). I will discuss their effectiveness in the following section.
How Much Vitamin D Do You Need?
Well, if you can get enough sun on your skin as described above, you really do not have to worry about getting more vitamin D from food and supplements.
On the other hand, food and supplements can provide a healthy dose of vitamin D if you have any (or a combination) of the following risk factors for low vitamin D:
- You do not spend enough time outdoors, especially in the sun.
- You live in a northern latitude, especially north of the Philadelphia-San Francisco line. For example, in Boston, there is not enough sunlight to make vitamin D in your skin for about 4 months of the year. If you go further north to Edmonton, Canada, your skin cannot make vitamin D for 5 months of the year.
- You have been following your dermatologist's suggestion of liberally using sunscreen to protect yourself from the sun's radiation.
- You have darker skin. Skin pigment reduces the skin's ability to absorb the ultraviolet radiation in the sun. In a bathing suit, a light-skinned person spending 10-12 minutes under peak July sun in Boston can make 10,000 to 20,000 international units of vitamin D. It will take an Asian Indian person, who has darker skin, about 30 minutes to make as much vitamin D. It will take an African American with very dark skin about 120 minutes to make the same amount of vitamin D.
- You are obese. Fat cells hoard vitamin D. This reduces the circulating vitamin in your blood.
- Your have a medical condition such as Crohn's disease, celiac disease, and cystic fibrosis that impairs your gut's absorption of vitamin D.
- You are a strict vegetarian.
- Your kidneys are impaired so they cannot activate the vitamin D you have.
- You are older than 65. This means your skin makes less vitamin D, your gut may not absorb nutrients as efficiently, and your kidneys may not activate vitamin D as effectively. Even in sunny South Florida, as many as 40% of older people have low vitamin D levels.
If you have any of these risk factors, how many international units of vitamin D should you aim for a day?
This depends on whom you talk to. In recent years, various scientific authorities came up with different amounts of vitamin D that they consider good for your daily intake through food and supplements.
To spare you the confusing numbers and arguments, here is the bottom line.
If you are an adult, aim for 600 to 2000 IUs of vitamin D a day from your food and supplements.
And if you get vitamin D from supplements, keep in mind that unit for unit, cholecalciferol (vitamin D3) is better used by your body than ergocalciferol (vitamin D2).
In general, vitamin D3 is about 3 times more powerful than vitamin D2.
How Do You Know if You are Vitamin D Deficient?
If you are low on vitamin D, you may have bone pain and muscle weakness. But, often the symptoms of low vitamin D are very subtle. And even without any clear symptoms, low vitamin D can badly affect your health in different ways.
Your doctor can order a simple blood test, 25-hydroxy vitamin D, for you. Again, the normal range for vitamin D also varies according to different authorities. But here is what you need to know: a level of 30 to 50 ng / mL is considered optimal for bone health and overall health.
If your blood test suggests that you are very low on circulating vitamin D, your doctor may give you a prescription for high-dose treatment for a period of time. Make sure you follow his or her directions.
Can You Get Sick From Too Much Vitamin D?
Yes you can!
Too much vitamin D in your body can make you not want to eat, lose weight, urinate excessively, and have abnormal heartbeats. Even more seriously, it can make your blood calcium level too high, resulting in damage to your heart, blood vessels, and kidneys.
Unless you are under close monitoring by you doctor, do not take over 4000 international units of vitamin D from food and supplements a day. Exceeding this dose will increase your risk for having a toxic overload of vitamin D.
On the other hand, your skin will not make too much vitamin D from sunshine. Your body is such a marvelous creation that when you get too much sun, your skin actually rids itself of the extra vitamin D automatically.
Keep reading to discover the keys for defusing ticking health bombs that could be lurking in your body. Click here to discover the medical secrets necessary to know so you can live a better, longer, healthier life.