Low Energy? How Vitamin D and Sunlight Affect Your Thyroid and Metabolism

As the colder months set in, many of us feel our energy levels start to dip. Winter can bring on that “low battery” feeling, leaving us more fatigued and even struggling with mood changes. But did you know that one of the reasons behind this seasonal slump could be low Vitamin D levels and reduced sunlight exposure? These two factors are essential for keeping our thyroid health and energy levels steady.

Vitamin D, known as the “sunshine vitamin,” plays a key role in our body’s ability to produce and convert thyroid hormones, which power our metabolism and energy. This guide explores the vital connection between Vitamin D, sunlight, and thyroid function. We’ll dive into why these elements are so important and offer practical tips for keeping energy levels high, even when the sun is scarce.

Vitamin D’s role in thyroid function and energy

The thyroid gland, a small yet mighty organ in the neck, helps regulate metabolism and energy. It produces two key hormones: T4 (thyroxine) and T3 (triiodothyronine). T4 is the inactive form, and it’s converted into T3, the active hormone that fuels cellular energy and metabolic processes. But here’s the catch-without enough Vitamin D, this conversion process can slow down, leading to lower T3 levels and the classic symptoms of hypothyroidism, including fatigue, weight gain, and low energy.

Vitamin D isn’t just important for this conversion; it also supports immune function and mood, making it even more essential during winter, when we’re prone to colds and flu, and our mood can take a hit. Reduced sunlight in winter means our natural Vitamin D production takes a dip, and this affects our thyroid, metabolism, and overall energy.

How Vitamin D deficiency impacts thyroid health

Studies show that low Vitamin D levels are often linked with low T3 levels and higher thyroid-stimulating hormone (TSH) levels, which suggests that the thyroid is struggling to function. Without sufficient Vitamin D, the thyroid can’t produce enough T3, leading to that sluggish, low-energy feeling we dread. This is why maintaining healthy Vitamin D levels, particularly during winter, is crucial for feeling alert and energised.

The impact of sunlight on circadian rhythm and thyroid health

Sunlight does more than just boost Vitamin D production; it also plays a key role in maintaining our circadian rhythm-our body’s internal clock that regulates sleep, energy, and mood. This rhythm influences not only our energy levels but also how well our thyroid hormones function.

The hypothalamus-pituitary-thyroid (HPT) axis is the system that controls thyroid hormone production. Sunlight exposure, especially in the morning, helps regulate this axis by stabilizing TSH (thyroid-stimulating hormone) levels. When we get enough sunlight, particularly in the morning, it sets off a chain of signals to keep thyroid hormones balanced, which supports both energy and mood.

How winter disrupts the HPT axis

During the winter, lack of sunlight disrupts our circadian rhythm and can affect the HPT axis, leading to irregular TSH secretion. This disruption impacts thyroid function and can leave us feeling fatigued, low in energy, and even more susceptible to seasonal affective disorder (SAD).

Studies suggest that reduced light exposure can lead to lower T3 levels and higher levels of TSH, which disrupts energy and mood regulation. In the Southern Hemisphere, Vitamin D levels are often at their lowest between August and October, so it’s a good idea to get your Vitamin D tested in these low-sunlight months.

Winter hacks for boosting Vitamin D and supporting thyroid health

With sunlight at a premium in winter, here are some easy ways to keep Vitamin D levels up and support your thyroid naturally.

1. Prioritise sunlight exposure

Aiming for 8-15 minutes of direct sunlight on exposed skin each day can help boost Vitamin D levels. Even on overcast days, a brief outdoor break can help. If you can, make a habit of stepping outside in the morning-whether it’s for a walk, a coffee break, or just sitting on a sunny patio. Activities like taking phone calls outside or eating lunch in the sun are great ways to build more natural light into your day.

2. Include Vitamin D-rich foods

While sunlight is the most effective source, dietary Vitamin D is a great way to help fill the gap during winter. Here are some of the best Vitamin D-rich foods to include:

• Fatty fish: Salmon, mackerel, and sardines are high in Vitamin D and omega-3s, with salmon providing about 570 IU of Vitamin D per 100g.
• Cod liver oil: Just one teaspoon of cod liver oil offers around 400 IU of Vitamin D, along with Vitamin A and omega-3 fatty acids. In fact, cod liver oil was traditionally used to help people through winter months because of its immune-boosting properties.
• Sun-exposed mushrooms: Leaving mushrooms in sunlight for 30 minutes to 2 hours can significantly increase their Vitamin D content-simply leave them out on the kitchen counter for a bit before cooking.
• Egg yolks: Each yolk contains about 37 IU of Vitamin D, making eggs an easy addition to winter meals.
• Grass-fed dairy: Dairy products from grass-fed cows are higher in Vitamin D. A cup of whole milk provides about 150 IU, while a tablespoon of butter has around 60 IU.

3. Supplement with Vitamin D3 and K2

A Vitamin D3 and K2 supplement can help fill in any dietary gaps during winter. D3 is the form of Vitamin D our bodies make from sunlight, so it’s the best option for supporting Vitamin D levels. K2 helps with Vitamin D absorption and ensures calcium is directed to the bones, supporting both cardiovascular and thyroid health. Together, D3 and K2 are a powerhouse for winter wellness.

Other nutrient deficiencies that can impact energy levels

While Vitamin D is key for thyroid function, other nutrient deficiencies can also drain your energy. Here are a few to keep in mind:

1. Vitamin B12

Vitamin B12 supports energy by helping with red blood cell production and neurological health. Low B12 levels can lead to anemia, fatigue, and brain fog. Animal-based foods like meat, eggs, and dairy are rich in B12, so if you’re vegetarian or vegan, consider a B12 supplement to keep levels up.

2. Iron

Iron is essential for oxygen transport in the blood, and low levels can lead to fatigue, pale skin, and shortness of breath. Include iron-rich foods like spinach, lean red meat, and legumes in your diet. If you struggle to absorb iron, try pairing it with Vitamin C-rich foods, such as capsicums or citrus fruits, which can boost absorption.

3. Magnesium

Magnesium is needed for energy production, muscle relaxation, and sleep quality. If you’re feeling tired, achy, or experiencing poor sleep, low magnesium levels could be to blame. Dark leafy greens, nuts, seeds, and even dark chocolate are good sources of magnesium, making it an easy nutrient to add to your winter diet.

These nutrients all work together with Vitamin D to support energy and thyroid function, so it’s worth checking your levels and considering supplements if needed.