Top up your Vitamin D this summer

Having a low level of vitamin D is linked with breast cancer. Making sure you have a healthy level of Vitamin D is a great way to stay well and may reduce your risk of breast cancer.

Vitamin D is naturally present in some foods (e.g. oily fish such as salmon, sardines, herring and mackerel, and egg yolks), added to others (e.g. breakfast cereals and non-dairy milk) and available as a dietary supplement.

But your main source of vitamin D is sunlight. When the sun’s rays interact with skin, vitamin D synthesis is triggered.

Vitamin D is a nutrient you need for good health. It helps the body absorb calcium, one of the main building blocks for strong bones.

How could vitamin D lower breast cancer risk?
In some studies, vitamin D has been found to slow or prevent the development of breast cancer. It also has anti-inflammatory benefits and decreases oestrogen synthesis. It is also important for a properly functioning immune system and may help protect against cancer spreading.

How much vitamin D should you have?

Your vitamin D level depends on several lifestyle habits, e.g. how much time you spend outdoors, what you eat, what medications you take, but also on your age and skin type.

Most people in the northern hemisphere can make enough vitamin D from being out in the sun daily for short periods with their forearms, hands or lower legs uncovered and without sunscreen, from late March to the end of September.

During winter and autumn, you need to get vitamin D from your diet because the sun is not strong enough for the body to make enough.

We recommend you get vitamin D from food sources rather than supplements, but if you can’t, consider taking a daily supplement containing 10 micrograms of vitamin D (400 IU).

While you can’t get too much vitamin D through sunshine, you can get too much vitamin D through supplements, which can lead to health problems.  Getting more than 4,000 IU per day (100 micrograms/day) increases the risk of harmful health effects, for example, kidney damage.

Making sure you have healthy levels of vitamin D is important for breast cancer prevention, but also good for your general.

BCUK recommends you be mindful about your vitamin D status and if you have any concerns get your levels checked by your GP, so you can determine if you need to take in more vitamin D either through sun exposure, or if this isn’t possible, though food or supplements.

Check out our Prevention Hub for my breast cancer prevention tips.

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References

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