Have you ever seen pictures of children with extremely bow legs? It is a condition called rickets and is due to low levels of vitamin D, which causes the bones to soften and weaken.

Vitamin D is crucial for bone health. It helps your body maintain a good balance of calcium and phosphate in your blood. With low levels of vitamin D, children can develop rickets and adults can develop osteomalacia, a condition in which weak bones lead to 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 cancers.

Nursing home residents appear to have significantly fewer falls when they start taking a daily vitamin D supplement.

While the jury is still out on all the studies related to vitamin D, we know that it’s essential that you have enough but not too much 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 to get vitamin D:

1. Your skin produces 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 of thumb, exposing your face, hands, arms, and legs to sunlight 2-3 times a week can produce enough vitamin D to keep you healthy. The exposure should be about 1/4 the amount of time it takes to get a mild sunburn. Depending on your skin color, this can mean 5 to 30 minutes of sun exposure between 10 am and 3 pm.

It is the ultraviolet B radiation in sunlight that helps the skin produce vitamin D. Full cloud cover reduces this radiation by about 50%. Shade, including shade from severe pollution, reduces this ultraviolet B radiation by about 60%.

What about the food?

Surprisingly, there aren’t too many foods that are naturally high in vitamin D. The following list includes foods that are highest in vitamin D:

Vitamin D measured in IU:

Cod liver oil, 1 tablespoon, 1,360

Swordfish, cooked, 3 oz., 566

Sockeye salmon, cooked 3 oz., 447

Mackerel, canned, 3 oz., 214

Sardines, canned, 3 oz., 197

Tuna, canned in water, drained, 3 oz., 154

Orange juice fortified with vitamin D, 1 cup, 137

Milk, fortified with vitamin D, 1 cup, fat-free, reduced-fat, and whole, 115-124

The abbreviation IU stands for “international unit” and is what you’ll find on food and supplement labels.

The third source of vitamin D is supplements.

There are generally two different forms of vitamin D on the market: ergocalciferol (also known as vitamin D2) and cholecalciferol (also known as D3). I will discuss its effectiveness in the next section.

How much vitamin D do you need?

Well, if you can get enough sun on your skin as described above, you really don’t have to worry about getting more vitamin D from food and supplements.

On the other hand, foods 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 don’t 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 produce vitamin D in the skin for about 4 months of the year. If you go further north to Edmonton, Canada, your skin can’t make vitamin D for 5 months of the year.
• You have been following your dermatologist’s suggestion to liberally use sunscreen to protect yourself from the sun’s radiation.
• You have darker skin. Skin pigment reduces the skin’s ability to absorb ultraviolet radiation from the sun. In a bathing suit, a fair-skinned person spending 10 to 12 minutes in the July sun in Boston can produce between 10,000 and 20,000 international units of vitamin D. An Asian Indian person, who has darker skin , it will take about 30 minutes to make that 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 accumulate vitamin D. This reduces the circulating vitamin in the blood.
• You have a medical condition such as Crohn’s disease, celiac disease, and cystic fibrosis that affects intestinal absorption of vitamin D.
• You are a strict vegetarian.
• His kidneys are impaired so they can’t activate the vitamin D he has.
• You are over 65 years old. This means your skin makes less vitamin D, your intestines may not absorb nutrients as efficiently, and your kidneys may not activate vitamin D as effectively. Even in sunny South Florida, up to 40% of seniors have low vitamin D levels.

If you have any of these risk factors, how many international units of vitamin D should you consume per day?

This depends on who you talk to. In recent years, various scientific authorities have proposed different amounts of vitamin D that they consider to be good for your daily intake through food and supplements.

To spare you the confusing numbers and arguments, here is the final result.

If you’re an adult, try to get 600 to 2,000 IU 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, your body uses cholecalciferol (vitamin D3) better than ergocalciferol (vitamin D2).

In general, vitamin D3 is about 3 times more potent than vitamin D2.

How do you know if you are deficient in vitamin D?

If you are low on vitamin D, you may have bone pain and muscle weakness. But often the symptoms of low vitamin D levels are very subtle. And even without clear symptoms, low vitamin D levels can seriously affect your health in a number of ways.

Your doctor may order a simple blood test, 25-hydroxy vitamin D. Again, the normal range for vitamin D also varies by different authorities. But here’s 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 have too little circulating vitamin D, your doctor may prescribe a high-dose treatment over a period of time. Be sure to follow their instructions.

Can You Get Sick From Too Much Vitamin D?

If you can!

Too much vitamin D in your body can cause you to not want to eat, lose weight, urinate excessively, and have abnormal heartbeats. Even more serious, it can make your blood calcium level too high, which can damage your heart, blood vessels, and kidneys.

Unless closely monitored by your doctor, take no more than 4,000 international units of vitamin D from food and supplements per day. Exceeding this dose will increase your risk of having a toxic vitamin D overload.

On the other hand, your skin won’t make too much vitamin D from the sun. Your body is such a wonderful creation that when it gets too much sun, your skin automatically gets rid of the extra vitamin D.

Read on to discover the keys to defusing health bombs that might be lurking in your body. Click here to discover the medical secrets needed to live a better, longer and healthier life.