Vitamin D - Strong Bones

Vitamin D is a fat-soluble vitamin that your body needs for many essential functions, most importantly helping you absorb calcium to build and maintain strong bones. It's sometimes called the “sunshine vitamin” because your skin can produce it when exposed to sunlight. Unlike many other vitamins, vitamin D functions more like a hormone and affects multiple systems in your body.

In this post, we’ll break down exactly what Vitamin D does, what happens when you don’t get enough, and how to boost your intake naturally through food and supplements.

How Vitamin D Works in the Body

Once vitamin D enters your body - either through your skin, food, or supplements - it must be converted into its active form through a process involving the liver and kidneys. The active form of vitamin D (called calcitriol) helps regulate calcium and phosphate levels in the bloodstream. These minerals are essential for healthy bones, teeth, and muscles.

Vitamin D also plays an important role in supporting the immune system, improving muscle function, and even influencing mood and mental health. Some research suggests that adequate vitamin D levels may help reduce the risk of chronic diseases such as heart disease, certain cancers, and autoimmune conditions.

Signs and Risks of Vitamin D Deficiency

Vitamin D deficiency is quite common, especially in people who get little sun exposure, wear full body coverings, have darker skin, or live in northern climates. Certain health conditions and obesity can also increase the risk.

Common signs of vitamin D deficiency include:

• Fatigue

• Bone pain or weakness

• Frequent infections

• Muscle aches

• Mood changes like depression

Long-term deficiency can lead to osteomalacia (soft bones) in adults and rickets in children. It also increases the risk of osteoporosis and bone fractures later in life.

Where to Get Vitamin D Naturally?

The best natural source of vitamin D is sunlight. When your skin is exposed to UVB rays, it produces vitamin D. However, how much you produce depends on skin tone, time of day, season, and location. Just 10–30 minutes of sunlight a few times a week may be enough for most people.

Food sources of vitamin D include:

• Fatty fish (salmon, mackerel, sardines)

• Egg yolks

• Beef liver

• Fortified foods (milk, cereals, orange juice, plant-based milks)

• Cod liver oil

If you don’t get enough sun or dietary sources, supplements can help maintain healthy levels.

How Much Vitamin D Do You Need Per Day?

The recommended daily intake of vitamin D depends on your age and life stage:

• 0–12 months: 400 IU (10 mcg)

• 1–70 years: 600 IU (15 mcg)

• Over 70 years: 800 IU (20 mcg)

Some experts suggest that many adults may benefit from higher doses—around 1,000–2,000 IU daily—especially during winter or if they have limited sun exposure. However, it's best to consult a doctor before taking high doses long-term, as too much vitamin D can be harmful.