Vitamin D Benefits

1. Vitamin D may fight disease

In addition to its primary benefits, research suggests that vitamin D may also play a role in:

• Reducing the risk of multiple sclerosis (MS).A 2018 review of population-based studies found that low levels of vitamin D are linked with an increased risk ofMS( 2 ).
• Decreasing the chance of heart disease.Low vitamin D levels have been linked to increased risk of heart diseases such as hypertension, heart failure, and stroke. But it’s unclear whether vitamin D deficiency contributes toheart diseaseor simply indicates poor health when you have a chronic condition ( 3 ).
• Reducing the likelihood of severe illnesses.Although studies are mixed, vitamin D may make severe flu and COVID-19 infections less likely. A recent review found that low vitamin D levels contribute to acute respiratory distress syndrome ( 4 , 5 ).
• Supporting immune health.People who do not have adequate vitamin D levels might be at increased risk of infections and autoimmune diseases, such as rheumatoid arthritis, type 1 diabetes, and inflammatory bowel disease ( 6 ).

2. Vitamin D may regulate mood and reduce depression

Research has shown that vitamin D might play an important role in regulating mood and decreasing the risk ofdepression.

A review of 7,534 people found that those experiencing negative emotions who received vitamin D supplements noticed an improvement in symptoms. Vitamin D supplementation may help people with depression who also have a vitamin D deficiency ( 7 ).

Another study identified low vitamin D levels as a risk factor for more severefibromyalgiasymptoms,anxiety, and depression ( 8 ).

3. It might support weight loss

更高的身体重量更有魅力的人nce of low vitamin D levels ( 9 ).

In one study, people with obesity who received vitamin D supplements in addition to following a weight lossdiet planlost more weight and fat mass than the members of the placebo group, who only followed the diet plan ( 9 ).

In an older study, people taking daily calcium and vitamin D supplements lost more weight than subjects taking a placebo supplement. The researchers suggest that the extra calcium and vitamin D may have had an appetite-suppressing effect (10).

The current research doesn’t support the idea that vitamin D would cause weight loss, but there appears to be a relationship between vitamin D and weight.

Vitamin D deficiency

Several factors can affect your ability to get adequate vitamin D from sunlight alone.

You may be less likely to absorb enough vitamin D from the sun if you ( 1 ):

• live in an area with high pollution
• usesunscreen
• spend most of your time indoors
• live in a big city where buildings block sunlight
• have darker skin (The higher the levels of melanin, the less vitamin D your skin can absorb.)

这些因素可以增加维生素D的风险deficiency. That’s why it’s important to get some of your vitamin D from non-sunlight sources.

What are the symptoms of vitamin D deficiency?

The symptoms of a vitamin D deficiency in adults may include ( 1 ):

• tiredness, aches, and pains
• severeboneor muscle pain or weakness
• stress fractures, especially in your legs, pelvis, and hips

A healthcare professional can diagnose avitamin D deficiencyby performing a simple blood test. If you have a deficiency, your doctor may order X-rays to check the strength of your bones.

If you receive a diagnosis of vitamin D deficiency, a healthcare professional will likely recommend that you take vitamin D supplements. If you have a severe deficiency, they may instead recommend high dose vitamin D tablets or liquids.

You should also make sure to get vitamin D through sunlight and the foods you eat.

Risks of getting too much vitamin D

If you take excessive amounts of vitamin D supplements, you may get too much of it. However, this is unlikely to happen through diet orsun exposurebecause your body regulates the amount of vitamin D produced through sun exposure.

Vitamin D toxicity can lead to an increase in your blood calcium levels. This can result in a variety of health issues, such as ( 11 ):

• nausea
• apathy
• vomiting
• abdominal pain
• dehydration
• confusion
• increased thirst

Some food sources of vitamin D

Some foods contain vitamin D naturally, and others are fortified with it. You can find vitamin D in the following foods ( 1 ):

• salmon
• sardines
• herring
• canned tuna
• cod liver oil
• beef liver
• egg yolk
• shrimp
• regular mushrooms and those treated with ultraviolet light
• milk (fortified)
• certain cereals and oatmeals (fortified)
• yogurt (fortified)
• orange juice (fortified)

It can be hard to get enough vitamin D each day through sun exposure and food alone, so taking vitamin D supplements could help.

How much do you need?

There has been some debate over the amount ofvitamin Drequired for optimal functioning. Recent studies indicate that we need more vitamin D than previously thought.

Some of the main controversies surrounding vitamin D are ( 11 , 12 ):

• standardization of methods for measuring vitamin D levels
• the difference between free and total vitamin D testing
• defining low vitamin D status (insufficiency versus deficiency)
• screening versus treatment
• vitamin D threshold for the general population relative to a particular condition (such as pregnancy or breastfeeding) and health issues (such as kidney failure or osteoporosis)

Blood serum levels considered adequate range from 50–100 nanomoles per liter (nmol/L). Depending on your blood level, you may need more vitamin D.

The Recommended Dietary Allowances for vitamin D are as follows ( 1 ):

• infants (0–12 months): 10 mcg (400 IU)
• children and teens: 15 mcg (600 IU)
• adults ages 18–70: 15 mcg (600 IU)
• 70岁以上成年人:20微克(800 IU)
• pregnant or breastfeeding women: 15 mcg (600 IU)

The bottom line

Vitamin D has many potential benefits. It may reduce the risk of certain diseases, help improve mood and reduce depression symptoms, and help with weight management.

It’s hard to get enough vitamin D through your diet alone, so you may want to ask a healthcare professional for a blood test and consider taking a vitamin D supplement.