The content in this article is intended for general educational purposes only. Please consult with your doctor regarding your personal health situation.

If you’re tired and cranky, the culprit might be more than your hectic schedule. Vitamin D deficiency affects an estimated 1 billion people worldwide and up to 35% of adults in the US. But because its symptoms are non-specific, the condition often goes undetected.

This is an essential issue for those of us in middle age. As our bodies undergo significant transitions, Vitamin D deficiency can impact our current and future health.

The Lowdown on Vitamin D

Vitamins are micronutrients that the body needs to function correctly but can’t synthesize on its own. Vitamin D, for example, is essential for bone health, muscle function, cell growth, and immune system regulation.

The natural sources of Vitamin D are diet and ultraviolet light (UVB) from sunlight. It’s also available as an oral supplement.

There are two forms of Vitamin D:

Vitamin D3 (Cholecalciferol): This is the natural form that your body makes from sunlight. The body more readily absorbs D3, so it’s the recommended type for over-the-counter supplementation.

Vitamin D2 (Ergocalciferol): This form is synthesized by plants and can be found in some plant-based foods. D2 is sometimes a prescription supplement, but it’s less effective than D3 in raising vitamin D blood levels.

Unused Vitamin D is stored in fatty tissue and the liver in case it’s needed later.

Factors Contributing to Midlife Vitamin D Deficiency

Decreased Sun Exposure

Our current lifestyle means more time indoors, which can significantly impact vitamin D levels.

Age-related skin changes

During midlife, the skin becomes thinner and less able to synthesize vitamin D.

Diet

Remember those “Got Milk?” campaigns? Or the California cow commercials? It wasn’t that long ago that milk was all the rage. When I was young, I drank milk at every meal (as well as cold milkshakes on a hot summer day. Heaven!)

Times have changed, and it’s estimated that up to 90% of Americans don’t get enough dairy in their diets. Milk’s fall from grace highlights a question debated for thousands of years: Is milk really necessary?

Milk does have its benefits, providing not only Vitamin D but also Vitamin A, calcium, and protein. But there are other sources of these nutrients in a well-balanced diet. So, where you get your nutrition isn’t all that important (sorry, California cows!)

Other Factors

Age, darker skin, obesity, and living in northern latitudes can predispose to vitamin D deficiency. Individuals with intestinal conditions like Crohn’s disease and celiac disease might also be prone to low levels.

Signs & Symptoms of Vitamin D Deficiency

Some of the more common presentations include:

Chronic fatigue unresolved after sleep

Muscle weakness, aches, and cramps

Mood changes, especially depression

Joint pain

Bone fractures

Hair loss

Frequent Infections, especially respiratory tract infections

Because these signs and symptoms are nonspecific, vitamin D deficiency can be challenging to diagnose. Hair loss, for example, can result from many other conditions. That’s why a blood test is needed to make a definitive diagnosis.

Special Relevance in Midlife

As our bodies transition into the next phase of our lives, it's crucial to establish a foundation for good health. Low Vitamin D levels can lead to issues with:

Bones

Midlife is crucial for bone health, especially for postmenopausal women. Without enough vitamin D, our bodies struggle to absorb calcium efficiently. This can lead to decreased bone mineral density, osteopenia, osteoporosis, and bone fractures.

Cardiovascular System

Vitamin D helps to regulate blood pressure and reduce cardiovascular inflammation. Research suggests a link between vitamin D deficiency in midlife and an increased risk of hypertension, heart attack, and stroke.

Mental Health

Vitamin D deficiency is associated with depression and cognitive impairment. Menopause, as well as stressors such as life transitions or other health issues, can further exacerbate these mood disorders.

Metabolic Syndrome

Metabolic syndrome is a group of conditions that raise the risk of developing heart disease, diabetes, and stroke. The five main components of metabolic syndrome are high blood pressure, obesity, low HDL cholesterol levels, high triglyceride levels, and insulin resistance.

In general, metabolic disorders become more common during midlife. Vitamin D deficiency has also been linked to an increased metabolic syndrome risk, further compounding the problem.

Immune System

Vitamin D deficiency may increase vulnerability to infections and illnesses. This can be problematic as our immune system becomes less effective with age.

Brain Health

middle aged woman closing her eyes and in discomfort

Studies have linked low vitamin D levels to cognitive issues and even dementia. Given that the risk of such conditions increases with age, adequate vitamin D levels might be particularly important to keep your brain working its best during midlife.

Risk of Cancer

Breast: Research suggests that low vitamin D levels might increase the risk of breast cancer, especially in postmenopausal women. Vitamin D has anti-inflammatory properties and is thought to enhance the immune response and regulate cell growth.

Colorectal Cancer: Studies have consistently found a strong association with vitamin D deficiency and colorectal cancer in older adults.
Maintaining Adequate Vitamin D Levels

A healthy, balanced diet is a great way to prevent low vitamin D levels. Vitamin D-rich foods include:

fatty fish (salmon, sardines, halibut, mackerel, trout, swordfish, herring)
fortified orange juice
breakfast cereals
egg yolks
milk (cow and plant)
beef, especially liver

There’s some controversy in the medical community regarding the optimal amount of daily sun exposure. The time recommended in the sun without sunscreen is 5 to 30 minutes, depending on factors like skin tone and location. Other clinicians are concerned about the risk of skin cancer even with such short unprotected sun exposure.

Talk to your healthcare provider about how much daily sun exposure is best for you. And always consider wearing sunglasses outside to help prevent eye diseases such as cataracts.

Choosing Your Vitamin D Supplement

When deciding on a Vitamin D supplement, there are a few factors to consider:

1. Dosage: As a general rule, the recommended dietary allowance (RDA) for adults up to age 70 is 600 IU (International Units) and 800 IU for those over 70.

People with darker skin, obesity, intestinal conditions like celiac disease, or those living in northern latitudes might need higher doses.

If your healthcare provider suggests supplementation, ask what dosage they recommend.

Don’t increase that dosage unless instructed – vitamin D toxicity can lead to serious side effects.

2. Forms: Vitamin D comes in a variety of preparations. Soft gels are often recommended as they enhance vitamin D absorption. If you prefer not to swallow pills, consider liquid drops.

Other forms include capsules, tablets, gummies, and chewable.

3. Ingredients and Allergens: Check for unnecessary additives like sugar, colorings, or preservatives. Gummies, for example, often contain added sugar to improve their taste.

Also, look for common allergens like gluten, dairy, soy, or corn.

If the vitamin D preparation includes a carrier oil, make sure it’s high-quality, like olive or coconut oil.

4. Certifications: Over-the-counter vitamins and supplements are not regulated by the FDA. Look for verification by third-party organizations such as USP (United States Pharmacopeia), NSF International, or ConsumerLab. If you’re concerned about the sourcing of ingredients, also check for Non-GMO Project Verified or USDA Organic designations.

5. Cost: Expensive doesn’t always mean better. Sometimes, that higher cost is due to marketing and packaging, not quality. Consider a reasonably priced supplement from a reputable brand with good reviews.

Too Much of a Good Thing….

When it comes to vitamins, more is not necessarily better. Your body naturally stores vitamin D, which is why it is important to check your level before starting or changing the dose of over-the-counter supplements. Too much vitamin D leads to hypercalcemia, which can cause nausea, vomiting, weakness, and even kidney damage or heart arrhythmia.

If you suspect you might be suffering from vitamin D toxicity, stop taking the supplement and contact your healthcare provider.

Wrapping Things Up

Maintaining your Vitamin D level within the normal range is essential to feeling your best. But there’s nothing that says you can’t enjoy it too! These smoothie recipes will help bring some yum to the equation:

Orange Creamsicle Smoothie

1 cup vitamin D-fortified orange juice

1/2 cup Greek yogurt

1 frozen banana

1/2 teaspoon vanilla extract

1 tablespoon honey

Ice cubes (optional)

Instructions:

Add the ingredients to a blender. Blend on high until smooth. If the smoothie is too thick, add more orange juice to adjust the consistency. Serve immediately.

Berry Almond Smoothie

1 cup vitamin D fortified almond milk

1/2 cup fresh or frozen mixed berries (blueberries, strawberries, raspberries)

1 tablespoon almond butter

1 tablespoon chia seeds

1/2 frozen banana

- Ice cubes (optional)