What’s the Role of Calcium and Vitamin D?
Calcium and vitamin D are nutrients your body needs to function. Calcium is a mineral, and vitamin D is both a vitamin in foods you eat and a hormone that your body makes. Both nutrients help keep your bones and muscles healthy and help your nerves function.
Vitamin D also:
- Helps your body absorb calcium and another mineral called phosphorous
- Boosts your immune system
And calcium:
- Helps your blood flow through your blood vessels
- Helps hormones get into your bloodstream
If you have too little calcium, you could have weak bones (known as osteoporosis) or have a higher risk of fracturing your bones. If you don't get enough calcium from what you eat or supplements, your body pulls calcium from your bones, which is how your bones can weaken over time.
Low vitamin D also increases your risk of osteoporosis, since it helps your body absorb calcium. Too little vitamin D can lead to another condition called osteomalacia, which causes pain and weak bones and muscles.
It's rare, but if your child gets too little vitamin D, they could get a disease called rickets. Rickets causes bones to be weak, deformed, and painful.
Vitamin D is also essential for the health of your immune system, and low levels have been linked to:
- Multiple sclerosis
- Type 1 diabetes
- Cold and flu
- Autoimmune conditions, like rheumatoid arthritis and psoriasis
And research shows that low vitamin D might increase your risk of:
- Heart attack
- Stroke
- Heart disease
- Type 2 diabetes
- Problems with thinking skills
- Cancer
How Much Do You Need?
Here's how much calcium and vitamin D you need every day:
Vitamin D recommended dietary allowance (RDA):
| Age | Male | Female |
|---|---|---|
| 0-12 months | 10 mcg (400 IU) | 10 mcg (400 IU) |
| 1–13 years | 15 mcg (600 IU) | 15 mcg (600 IU) |
| 14–18 years | 15 mcg (600 IU) | 15 mcg (600 IU) |
| 19–50 years | 15 mcg (600 IU) | 15 mcg (600 IU) |
| 51–70 years | 15 mcg (600 IU) | 15 mcg (600 IU) |
| >70 years | 20 mcg (800 IU) | 20 mcg (800 IU) |
Calcium recommended dietary allowance (RDA):
| Age | Male | Female |
|---|---|---|
| 0–6 months | 200 mg | 200 mg |
| 7–12 months | 260 mg | 260 mg |
| 1–3 years | 700 mg | 700 mg |
| 4–8 years | 1,000 mg | 1,000 mg |
| 9–13 years | 1,300 mg | 1,300 mg |
| 14–18 years | 1,300 mg | 1,300 mg |
| 19–50 years | 1,000 mg | 1,000 mg |
| 51–70 years | 1,000 mg | 1,200 mg |
| >70+ years | 1,200 mg | 1,200 mg |
- Mg: milligrams
- Mcg: micrograms
- IU: international units
Your doctor may recommend higher levels of calcium and vitamin D, especially if you aren't getting enough of them or are at risk of getting osteoporosis.
Vitamin D-Rich Foods
While your body can make vitamin D from exposure to the sun, some foods naturally contain vitamin D, including:
- Wild-caught salmon (600-1,000 IU per 3.5 ounces)
- Farm-raised salmon (100-250 IU per 3.5 ounces)
- Canned sardines (300 IU per 3.5 ounces)
- Canned tuna (236 IU per 3.5 ounces)
- Fresh shiitake mushrooms (100 IU per 3.5 ounces)
- Egg yolk (20 IU per yolk)
Many foods and beverages – such as milk, orange juice, yogurt, baby formula, cereal, and cheese – often have vitamin D added to them when they're processed.
Vegan sources of vitamin D
Other than mushrooms, vegans don’t eat most of the foods in which vitamin D naturally occurs. If you’re vegan and don’t eat meat or any food that comes from animals (such as dairy products and eggs), you can rely on vitamin D supplements or plant-based foods or beverages fortified with vitamin D, such as:
- Soy, almond, or oat milk (100-144 IU per cup)
- Cereal (80 IU per serving)
- Margarine (60 IU per tablespoon)
- Orange juice (100-105 IU per cup)
High-Calcium Foods
Cow’s milk is the most well-known source of calcium, but the nutrient can be found in other foods, too, such as:
- Cooked kale (179 mg per cup)
- Cooked collard greens (266 mg per cup)
- Dried figs (65 mg per 2 figs)
- Cooked broccoli (60 mg per cup)
- Oranges (55 mg per orange)
- Canned sardines with bones (325 mg per 3 ounces)
- Canned salmon with bones (180 mg per 3 ounces)
- Ricotta (335 mg per 4 ounces)
- Low-fat plain yogurt (310 mg per 6 ounces)
- Milk (300 mg per 8 ounces)
- Greek yogurt (200 mg per 6 ounces)
- Cottage cheese (105 mg per 4 ounces)
Vegan sources of calcium
Even though vegans do not eat dairy products, if you follow a vegan diet, there are still many foods you can eat that are a good source of calcium. In addition to the fruits and vegetables in the above list, other calcium sources for vegans include:
- Canned baked beans (160 mg per 4 ounces)
- Cooked broccoli rabe (100 mg per cup)
- Cooked bok choy (160 mg per cup)
- Fortified almond, soy, or rice milk (300 mg per 8 ounces)
- Fortified fruit juices (300 mg per 8 ounces)
- Tofu prepared with calcium (205 mg per 4 ounces)
- Fortified cereal (100-1,000 mg per cup)
Vitamin D and Calcium Relationship
Your body needs vitamin D to absorb enough calcium from the food you eat. If you are severely lacking in vitamin D, even if you eat a lot of calcium-rich foods, you may have problems. The average person loses about 500 milligrams of calcium from their bones daily, but then replaces it with new calcium. But if you don’t have enough vitamin D, you won’t be able to replace enough calcium.
Without enough vitamin D and the inability to absorb, or use, calcium from food, your body might instead look to your bones for the calcium it needs. This can lead to a condition called secondary hyperparathyroidism. Depending on your age, this can cause rickets or osteoporosis, or problems with your muscles and balance, which could be a particular concern if you’re over 65.
Calcium and Vitamin D Supplements: Yes or No?
While you can get some vitamin D from being out in the sun, it’s generally considered unsafe to be out in the sun as long as you would need to be to get the recommended amount of vitamin D. It’s also difficult to get an adequate amount of vitamin D from the food you eat, so most doctors do recommend a vitamin D supplement if a blood test shows that your level is low.
A variety of things contribute to limiting the amount of vitamin D your body can create, such as if you:
- Live farther north than Louisiana
- Wear sunscreen when outside
- Have naturally dark skin
- Are older
Even if you eat a balanced diet, you may not get enough calcium if you:
- Are vegan
- Are lactose intolerant
- Eat high volumes of protein and sodium
- Take corticosteroids for long-term treatments
- Have certain bowel or digestive issues
In the above cases, your doctor may recommend that you take calcium supplements.
It's important to note that while too little calcium and vitamin D can be bad for your health, so can too much. Taking more calcium than you need can cause kidney stones, and very high levels of vitamin D can hurt your kidneys.
Best calcium and vitamin D supplements for osteopenia
Osteopenia is the medical term for loss of bone density. If it becomes bad enough, it can advance to osteoporosis. As part of your treatment plan, your doctor may advise you to take vitamin D and calcium supplements.
There are several types of calcium supplements:
- Carbonate
- Citrate
- Gluconate
- Lactate
Carbonate and citrate are the most common types of calcium supplements, with carbonate often being the cheapest. It’s important to pay attention to the amount of elemental calcium in the supplement. Since calcium supplements can cause side effects such as gas, bloating, and constipation, you may need to try more than one to find out which works best for you. Carbonate generally causes constipation more than the other calcium types.
Supplement companies can voluntarily have their products tested by the U.S. Pharmacopeial Convention (USP), ConsumerLab.com (CL) or NSF International. If the supplement container shows the USP, CL, or NSF abbreviation, that means it meets industry standards for quality, purity, and potency.
Some calcium supplements have vitamin D in them, too. So if your doctor has recommended you take both, a combo supplement may work for you. If you take a multivitamin, it may contain some vitamin D.
There are two types of vitamin D supplements: D2 (ergocalciferol) and D3 (cholecalciferol). They are both considered good for keeping your bones healthy.
Always talk to your doctor before starting or stopping a supplement. Vitamin D and calcium supplements might interact with some prescription drugs, so your doctor or pharmacist can also advise you on possible interactions.
Takeaways
Your body needs calcium and vitamin D to maintain healthy bones. You can get calcium from a variety of foods, and vitamin D from a few foods and being outside in the sun. If you are at risk of low levels of calcium and/or vitamin D, or a blood test shows that your levels are low, speak to your doctor about taking supplements.
FAQs About Calcium and Vitamin D in Food
What foods are high in calcium and vitamin D?
Calcium is found in leafy greens like kale and collard greens; canned seafood with bones; fruits such as figs and oranges; and dairy products such as milk, yogurt, and cheese.
Vitamin D is found in fatty fish, some types of mushrooms, and egg yolks.
Food manufacturers also fortify, or add in, vitamin D and calcium to foods they process.
How do you increase calcium and vitamin D?
You can boost your levels of calcium and vitamin D by eating foods that contain those nutrients, but it can be difficult to get as much as you need, especially vitamin D, through your diet alone. In that case, you can speak to your doctor about taking supplements to increase your calcium and vitamin D levels.
Which food has the highest calcium?
Dairy products, such as milk and plain yogurt, and canned sardines with bones provide the highest calcium levels per serving.
Which fruit is good for vitamin D and calcium?
Figs and oranges contain calcium, but fruit does not contain vitamin D.
