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Vitamin D3 Benefits for Women

Optimal health is more than just physical activity and eating healthy foods every now and then.

It’s about focusing on the nutrients that have the most positive impact on your well-being, vitality and longevity as well.

That way you’ll support your body to work optimally – and reap the rewards.

In this article we take a look at why, as a woman, vitamin D can benefit you – from boosting health to ramping up performance.

Read on to find out why the ‘sunshine vitamin’ is the most vital, but often overlooked nutrient around.

What is Vitamin D3?

Vitamin D is a fat-soluble vitamin that promotes health, well-being and physical performance.

It plays a major role in regulating the amount of phosphate and calcium in the body, as well as ensuring your muscles and immune system function properly too.

There is also research pointing out that this nutrient can help protect against metabolic diseases such as diabetes, heart disease and neurological diseases such as multiple sclerosis.

All-in-all, it’s a versatile and key vitamin.

There are two types of vitamin D:

  • Ergocalciferol or D2
  • Cholecalciferol – commonly referred to as D3

Vitamin D3 is often classed as the sixth steroid hormone because of its hormone-supporting properties. It is also the most potent and biologically active form of the vitamin too.

When you come into contact with the sun, your body makes its own D3.

That’s because exposure to UV rays from the sun triggers a cascade of chemical changes that help you convert cholesterol into steroid hormones such as estrogen, progesterone and testosterone.

But unless you live in a hot climate and get plenty of sun, you’ll have to rely on either food or a supplement containing the nutrient to get what you need.

The chances are you’re not getting enough vitamin D3

If your vitamin D levels are low, you could be suffering a number of health-related side effects.

And with 50% of people suffering from inadequate levels, this is a major worry – and a common issue.

One study even found that when you look specifically at women, that figure can go up as high as two-thirds [1].

You don’t have to rely on the sun for your vitamin shot – you can also get vitamin D3 from foods such as salmon, mackerel and other oily fish. But even then, it’s likely that you’re not getting enough to reach healthy amounts.

Vitamin d3 capsules in a spoon on a wooden background

Key Point: Many women suffer from vitamin D3 deficiency. It’s a concerning issue from both a health and physical performance perspective.

What Are the Benefits of D3 for Women?

By now you should have recognized that for overall health, vitamin D3 is essential.

But what about specifically for women? How is it beneficial?

#1. Stronger Bones

Vitamin D is needed for calcium absorption. Without it, as little as 10-15% of dietary calcium, and 60% of phosphorous are absorbed [1].

Without proper support from these minerals, bone strength can decrease and your risk of fractures and postural issues increases rapidly..

Bone diseases such as osteoporosis, osteopenia and osteolamalacia are all more common in females than in men.

One study found that a lack of vitamin D increased the risk of bone fractures by over 75% [2] – that’s a huge increase in risk just for missing out on a nutrient.

But don’t worry though, because other studies found that when you bring your vitamin D levels back to normal, the risk of bone diseases decreases.

In fact, one review study suggested that vitamin D is like the ‘bricks and mortar’ of bone cell formation [3] – it’s that important.

#2. Increased Fertility

One of the more ‘left field’ benefits of D3 is that it can help to boost fertility.

It has been shown to increase success during in-vitro fertilization, and also promote egg cell maturation during various stages of embryonic development.

Remember, vitamin D is involved in steroid hormone synthesis – and in women that includes production of estradiol and progesterone – both important in regulating fertilization.

Vitamin D deficiency has been linked to elevated infertility in a number of studies. In one of these, fertility reduced by as much as 75% when deficiency occurred [4].

#3. More Efficient Immune System

There’s a clear link between vitamin D and immune receptor efficiency.

It directly supports the production of white blood cell components such as B cells, T cells and antigen presenting cells – all of which help your body fight infection and invading organisms [5].

There are multiple clinical trials showing that lower levels of D3 result in an increase in common colds and other infections.

The largest of these studies found that in a sample of over 18,800 men and women, those with D3 levels falling below 30 ng.dL were significantly more likely to suffer from upper respiratory tract infections [6].

And another study found that correcting low vitamin D levels with a supplement resulted in a 42% decrease in seasonal flu during winter months in a sample of 167 people [7].

 #4. Decreases Risk of Female Cancers

Continuing with the immune system theme, vitamin D may have a mechanistic benefit to cancer prevention.

That’s because this versatile fat-soluble vitamin might helps to control the growth or ‘proliferation’ of cancer cells.

A large study published in the American Journal of Public Health [8] found that when 63 individual studies were analysed, the collective results showed a clear and significant relationship between vitamin D status and ovarian, breast and colon cancer. 

Nearly 70% of breast cancer suffers have low vitamin D levels.

#5. Lower Muscle Soreness

This one’s more about performance than health, but nevertheless it’s still important.

One of the biggest limiting factors in regular physical activity is the unrelenting soreness you can get from intense exercise.

But higher doses of vitamin D3 have been shown to accelerate the damage caused by vigorous exercise such as weight lifting or interval training.

For example, when a group of athletes were given 4,000 IU of D3 each day for 4 weeks, their muscle soreness reduced by 50% – a huge benefit for someone that wants to train hard on a regular basis [9].

Interestingly, vitamin D2 has been shown to increase muscle soreness as well as have a negative impact on D3 levels – so that’s definitely one supplement to avoid when it comes to making gains in the gym [10].

Woman in sportswear enjoying the sunrise on the beach


  1. Lappe, JM et al. Vitamin D status in a rural postmenopausal female population. J Am Coll Nutr. 2006; 25(5): 395-402
  2. Cauley, JA et al. Serum 25 HydroxyVitamin D Concentrations and the Risk of Hip Fractures: The Women’s Health Initiative. Ann Intern Med. 2009; 149(4): 242-250
  3. Sunyecz, JA. The use of calcium and vitamin D in the management of osteoporosis. Ther Clin Risk Manag. 2008; 4(4): 827-836
  4. Halloran, BP et al. Effect of Vitamin D Deficiency on Fertility and Reproductive Capacity in the Female Rat. J Nutr. 1980; 110(8): 1573-80
  5. Aranow, C. Vitamin D and the immune system. J Investig Med. 2011; 59(6): 881-886
  6. Ginde, AA et al. Association between serum 25-hydroxyvitamin D level and upper respiratory tract infection in the Third National Health and Nutrition Examination Survey. Arch Intern Med. 2009; 169(4): 384-90
  7. Urashima, M et al. Randomized trial of vitamin D supplementation to prevent seasonal influenza A in schoolchildren. Am J Clin Nutr. 2010; 91(5): 1255-60
  8. Garland, CF et al. The role of vitamin D in cancer prevention. Am J Public Health. 2006; 96(2): 252-261
  9. Barker, T et al. Supplemental vitamin D enhances the recovery in peak isometric force shortly after intense exercise. Nutr Metab (Lond) 2013; 10: 69
  10. Nieman, DC et al. Vitamin D2 Supplementation Amplifies Eccentric Exercise-Induced Muscle Damage in NASCAR Pit Crew Athletes. Nutrients. 2014; 6(1): 63-75