The Sunshine Vitamin

It’s been lovely to finally see some sunshine – at least down here in Dorset. Getting outside and feeling the warmth of the sun on our body can really boost our mood, and that could, in part, be down to its role in making vitamin D. While we can get some vitamin D through our diet, it’s the chemical reaction triggered by sunlight on our skin that is our body’s main source of this important vitamin.

Most of us learnt at school that we need vitamin D for good bone health. Deficiency can cause rickets in children and soft bones in adults, which is why the NHS advises all children under the age of five should take a supplement all year round and adults should consider taking one in the autumn and winter when we don’t get much sun [1]. But vitamin D does so much more than contribute to healthy bones.

Vitamin D plays a crucial role in our immune system. Recently, a number of studies have been carried out investigating the role of vitamin D deficiency in individuals’ response to Covid-19. They show that people who are vitamin D deficient are at a greater risk of developing Covid and having more severe symptoms than those who are not [2]. People who don’t get enough vitamin D from their diet or the sun are also more at risk of other respiratory tract infections [3].

Vitamin D has also been shown to benefit our gut microbiome. This is important because the gut microbiome impacts both our physical and mental health. It is still a relatively new area of research, but gut dysbiosis (an imbalance in the gut bacteria) [4] has been linked to a range of poor health outcomes, from digestive problems and skin conditions to anxiety and depression; it has even been shown to play a part in obesity [5]. A recent study found that giving vitamin D supplements to those who were deficient but otherwise healthy increased the diversity of their gut microbiota [6]. A lack of diversity has been linked to a number of chronic diseases, including diabetes (both type 1 and type 2) and irritable bowel syndrome [7].

Anxiety and major depressive disorder have also been associated with low vitamin D levels, though more research is needed to establish a firm link; however, it has been shown that vitamin D deficiency can increase the symptoms of anxiety and depression [8].

So should we all be taking supplements? The short answer is ‘no’. There are lots of factors affecting our ability to make vitamin D, the most important of which is our exposure to sunlight. The further north you live, the more likely it is that you won’t be getting enough sun. Skin colour also makes a difference – people of African or south Asian heritage may not make sufficient quantities from sunlight [1].

We can also use food to boost our vitamin D levels. Oily fish is a really good source, as are red meat and eggs [1]. However, if you can’t get outside every day, or don’t regularly eat these foods, it might be worth taking a supplement. It’s best to talk to your GP or a BANT-approved nutritional therapist first though. They can arrange for you to have your vitamin D levels tested and advise on a suitable dose. Taking too much can cause serious health problems, such as damage to the heart and kidneys, so it’s best to talk to a health professional before taking any vitamin D supplements.

The good news is, you can’t overdose on vitamin D from the sun, so take advantage of those bright spring days and soak up some goodness – your mind and body will thank you for it.

Sources

[1] NHS, ‘Vitamin D’, NHS. 2020 https://www.nhs.uk/conditions/vitamins-and-minerals/vitamin-d/#should-i-take-a-vitamin-d-supplement

[2] H Dissanayake et al., ‘Prognostic and therapeutic role of vitamin D in COVID-19: systematic review and meta-analysis’, in The Journal of Clinical Endocrinology and Metabolism. December 2021, https://doi.org/10.1210/clinem/dgab892.

[3] A Albergamo, G Apprato G and S Silvagno, ‘The role of vitamin D in supporting health in the COVID-19 era’, in Internationa Journal of Molecular Science. March 2022, https://doi.org/10.3390/ijms23073621.

[4] S Wei et al., ‘Determining gut microbial dysbiosis: a review of applied indexes for assessment of intestinal microbiota imbalances’, in Applied and Environmental Microbiology. May 2021,  https://doi.org/10.1128/AEM.00395-21.

[5] M Salvadori and G Rosso, ‘Update on the gut microbiome in health and diseases’, in World Journal of Methodology. March 2024, https://doi.org/10.5662/wjm.v14.i1.89196.

[6] P Singh et al., ‘The potential role of vitamin D supplementation as a gut microbiota modifier in healthy individuals’, in Scientific Reports. December 2020, https://doi.org/10.1038/s41598-020-77806-4.

[7] A Vijay and A Valdes, ‘Role of the gut microbiome in chronic diseases: a narrative review’, in European Journal of Clinical Nutrition. April 2022, https://doi.org/10.1038/s41430-021-00991-6

[8] S Akpinar and M Karadag, ‘Is vitamin D important in anxiety or depression? What is the truth?’, in Current Nutrition Reports. September 2022, https://doi.org/10.1007/s13668-022-00441-0.

Why Nutritional Therapy Means More Not Less

It’s easy to be overwhelmed by the contradictory messages we are all given about food. Scroll through social media, or even pick up an old-school magazine or newspaper, and you’re likely to be bombarded with articles about what you should or shouldn’t be eating to achieve optimal health/a perfect body/great skin/improved mental health…I could go on.

At its most basic, food is about energy and getting enough nutrients for your body to function properly. But it’s also much more than that. We use food to bring people together, to celebrate, to nourish, to comfort. Think of all the religious festivals, across many faiths, that end in a feast. We bake birthday cakes and mark special occasions with a meal out, we invite friends over for dinner, make nutritious soup if loved ones are poorly, crave warm comfort food in the winter and gather round the barbecue the moment the sun comes out. It would be such a shame to lose this enjoyment of food in a (probably) futile attempt to achieve some theoretical ideal.

The good news is, food really does have the power to make us feel physically better as well as happier. Broken down into its component parts – proteins, fats, carbohydrates, vitamins, minerals, antioxidant phytonutrients – food fuels every process in our body. Even better, the body loves variety, so the more different foods you eat, the better. A healthy diet isn’t necessarily about cutting things out, it’s about expanding your menu: eating a range of colourful fruits and vegetables, trying new grains, such as quinoa and buckwheat, adding different beans and pulses, like black beans, pinto beans and Puy lentils, eating nuts and seeds and being more adventurous with your choice of meat and fish. We are lucky in this country to have access to so many foods, even in the cheaper supermarkets, so it seems a shame to stick to the old favourites.

I am passionate about the effect good nutrition can have on our physical and mental wellbeing. I know from personal experience and from seeing the effect of nutritional therapy on members of my own family, that simple changes can have a huge impact. It’s not always easy. Our digestive system can be negatively affected by a range of things, from stress to poor sleep, environmental pollutants to too much ultra-processed food. It can take time to undo the damage to our gut microbiome, but ultimately adopting a varied diet high in plant food and good quality protein will not only make you feel better, but you’ll probably get more enjoyment from eating too, and that can only be a good thing.