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Sunshine From Within: Boost Gut Health & Immunity with Vitamin D

Updated: Mar 25


Emptying a vitamin capsule from a bottle

Vitamin D plays a crucial role in maintaining overall health and wellness, and recent research suggests that it may have a significant impact on gut health as well. This essential nutrient, which is often referred to as the "sunshine vitamin," is essential for strong bones, a healthy immune system, and proper functioning of the body's cells. However, recent studies have also shown that vitamin D may play a key role in maintaining a healthy gut microbiome, the collection of microorganisms that live in our intestines.


In this post we will show you how you can boost gut health & immunity with Vitamin D including the potential benefits and risks, and how to ensure you are getting enough of this vital nutrient. So, let's dive in and discover how vitamin D can help keep your gut healthy and functioning at its best.


The gut is home to a diverse community of microorganisms known as the gut microbiome. These microorganisms play a vital role in many bodily functions, including digestion, immunity, and metabolism. Recent studies have shown that vitamin D plays an important role in regulating the gut microbiome.


Vitamin D helps to maintain the integrity of the gut barrier, which is the lining of the gut that separates the inside of the gut from the rest of the body. This barrier serves as a barrier against harmful microorganisms and toxins, and it also helps to regulate the immune system. When the gut barrier is compromised, it can lead to a variety of health problems, including inflammation, autoimmune disorders, and infections.


Vitamin D also plays a role in regulating the balance of bacteria in the gut. Research has shown that low levels of vitamin D are associated with an overgrowth of harmful bacteria in the gut, while adequate levels of vitamin D can help to promote the growth of beneficial bacteria. This can help to improve digestion and absorption of nutrients, as well as support the immune system.


Vitamin D deficiency is common, especially in individuals who have limited sun exposure or who have darker skin pigmentation. Symptoms of vitamin D deficiency include fatigue, muscle weakness, and bone pain. To maintain optimal gut health, it is important to ensure that you are getting enough vitamin D through dietary sources or supplements. Good dietary sources of vitamin D include fatty fish, egg yolks, and mushrooms, and it is also added to some food and supplement products.


What is a regular maintenance dose of vitamin D?


Using a dropper to dispence Vitamin D

The recommended daily intake of vitamin D varies depending on a person's age, sex, and level of sun exposure. The Institute of Medicine (IOM) provides the following recommended daily intake of vitamin D:

  • Infants 0-12 months: 400-1000IU/day

  • Children 1-18 years: 600-1000IU/day

  • Adults 19-70 years: 600-800IU/day

  • Adults over 70 years: 800-1000IU/day

  • Pregnant and lactating women: 600-800IU/day

It's important to note that these are recommended daily intake and not maintenance dose. Maintenance doses can vary depending on an individual's needs, as determined by their healthcare provider. Blood tests can be done to check a person's vitamin D levels, and a healthcare professional can then recommend an appropriate dosage based on the results.


It's also worth mentioning that some people may need higher doses of vitamin D, particularly those with certain health conditions or who are at risk of deficiency. It's best to consult with a healthcare provider to determine the appropriate daily dosage for an individual.


It's important to not exceed the upper limit of vitamin D intake which is 4000IU/day for adults. High doses of vitamin D can lead to toxicity which can cause negative side effects such as nausea, vomiting, poor appetite, constipation, weakness, and weight loss.


What foods contain vitamin D?


A beautiful plate of Sushi

Vitamin D is a fat-soluble vitamin that is naturally present in very few foods, but it can be found in some fortified food products.


The best dietary sources of vitamin D include:

  • Fatty fish: such as salmon, tuna, mackerel, and sardines. These fish are also good sources of omega-3 fatty acids.

  • Egg yolks: contain moderate amounts of vitamin D.

  • Mushrooms: that have been exposed to UV light, such as shiitake and portobello mushrooms, can be a good source of vitamin D.

  • Beef liver: contains small amounts of vitamin D

  • Dairy products: such as milk, yogurt, and cheese are often fortified with vitamin D.

  • Fortified foods: such as cereal, orange juice, and some plant-based milk alternatives, are often fortified with vitamin D.

It's worth noting that even if you consume these foods regularly, it may be difficult to get enough vitamin D through diet alone, especially during the winter months or if you live in a place with limited sun exposure. It may be necessary to take a supplement or a multivitamin to ensure adequate intake.


What other supplements are beneficial for gut health?


The word probiotic spelt with scrabble tiles

There are several supplements that may be beneficial for gut health, depending on an individual's specific needs. Some of the most commonly recommended supplements for gut health include:

  • Probiotics: These are live microorganisms that can provide health benefits when consumed in adequate amounts. Probiotics can help to balance the gut microbiome, which can improve digestion and boost the immune system.

  • Prebiotics: These are non-digestible carbohydrates that can promote the growth of beneficial bacteria in the gut. They can be found in food sources such as bananas, onions, garlic, and asparagus. They are also available in supplement form.

  • Fibre: Fibre can help to promote regular bowel movements, and can also feed the beneficial bacteria in the gut. Fibre supplements such as psyllium husk and glucomannan can be helpful for those who do not consume enough fibre in their diet.

  • Digestive enzymes: These can help to break down food and improve digestion. Many are available as supplements, including pancreatin, bromelain, and papain.

  • Glutamine: This is an amino acid that can help to support the gut lining and improve gut barrier function.

It's important to note that gut health can be affected by a variety of factors, and what works for one person may not work for another. It's always best to consult with a healthcare professional before starting any new supplement regime, especially if you have any health conditions or are taking any medications.


Also, some supplements may interact with certain medications or have negative side effects, so it's important to check with a healthcare professional to determine if they are safe and appropriate for you.


Does Vitamin D help IBS sufferers?


A woman sat at a work desk feeling bloated

There is some evidence to suggest that vitamin D may be beneficial for individuals with Irritable Bowel Syndrome (IBS). Studies have shown that individuals with IBS tend to have lower levels of vitamin D compared to those without the condition. As previously stated, low levels of vitamin D have also been linked to increased inflammation in the gut, which is a key feature of IBS.


Research has shown that supplementing with vitamin D can help reduce symptoms of IBS such as abdominal pain, bloating, and diarrhoea.


It's important to note that while vitamin D may be beneficial for IBS sufferers, it is not a cure. It is also important to consult with a healthcare professional before starting a vitamin D supplement, as excessive intake can lead to toxicity.


It is also important to mention that vitamin D alone is not the solution for IBS, addressing the underlying causes of IBS such as stress, food sensitivities, and gut dysbiosis, through diet and lifestyle changes, and possibly working with a practitioner who specializes in gut health is crucial for managing and improving IBS symptoms.


In conclusion, vitamin D plays a crucial role in maintaining gut health by regulating the gut barrier and promoting the growth of beneficial bacteria. To ensure optimal gut health, it is important to ensure that you are getting enough vitamin D through dietary sources or supplements. If you suspect that you may be deficient in vitamin D, it is important to consult with a healthcare professional for further evaluation.


"This article represents the personal views and opinions of the author and should not be taken as representative of the official policy or position of any organization, professional, expert, or individual."

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