What foods contain vitamin D and how to make up for its deficiency? Vitamin D is the only nutrient that the body produces through sunlight. But its deficit can also be filled with a diet.
Foods rich in vitamin D
According to the USDA, a serving of oily fish weighing about 100 g contains 526 IU (international units) of vitamin D. This is 66% of the daily norm. A lot depends on where the salmon was raised. Fish caught in the wild contain up to 988 IU of vitamin D per serving, and some studies claim that this figure goes up to 1300 IU. Captive-bred salmon can provide 25% less nutrients, but on average, one serving provides 250 IU of vitamin, or 32% of the daily value.
Sardines and other oily fish
Canned sardines are a good source of “sun vitamin”. One hundred-gram serving contains 177 IU of the nutrient, which is 22% of the daily intake. Other types of healthy fatty fish should also be included in the diet if you spend a lot of time indoors. For example, a serving of halibut or mackerel will provide about 360-390 IU of vitamin D.
Herring is not only cooked in oil. It can be canned, smoked, or pickled. One fresh, natural Atlantic herring is a source of 216 IU of vitamin D per serving, or 27% of the recommended daily intake. If you prefer pickled fish, then use it to replenish about 14% of the required amount of vitamin D—in one serving of 112 IU. Keep in mind that this method of cooking fish accumulates a lot of salt, an excess of which can negatively affect your health.
This fish is often added to soups and salads. Canned food is convenient to store, and you can easily prepare lunch without long heat treatment. In addition, in this form, tuna is much cheaper than fresh. Canned food contains 268 IU of vitamin D per 100 g, which is 34% of the daily value. In addition, canned tuna is an excellent source of vitamin K. But doctors say the product may contain traces of mercury and other toxins that, when accumulated in the body, cause health problems. They are found in many types of fish , so you should not eat canned tuna every day.
Cod liver oil
The fat of this fish is used to prevent vitamin D deficiency in children. A teaspoon of cod liver oil contains 448 IU of the substance, which is 56% of the recommended daily value. In addition, this fat contains a large amount of omega-3 and vitamin A—about 150% of the daily norm in 5 ml. Keep in mind that large amounts of this vitamin can be toxic, so do not use cod liver oil too often.
Seafood is the main, but not the only source of vitamin D. Whole eggs make up for its deficiency as well, and they are also very nutritious. Useful substances and minerals are contained mainly in the yolk: in one—5% of the daily norm of “solar vitamin”. The amount of vitamin D depends mainly on the time the chicken has been exposed to the sun and the quality of the grain it has been fed. Farmed birds produce eggs that contain three to four times more nutrients.
Vitamin D is produced in fungi under the influence of ultraviolet radiation. This is one of the plant products with a high content of vitamins without additional artificial enrichment. Mushrooms have a lot of D2, while, for example, fish has a lot of D3. D2 helps increase blood vitamin levels, but it is less effective than D3. Some varieties of mushrooms contain up to 2300 IU in a hundred-gram serving, which is almost several times more than the daily norm. But most types of product from the store are grown in the dark, and they contain much less useful substances. Some manufacturers treat mushrooms with ultraviolet light, which provides about 130-450 IU of vitamin D2 per serving.
There are not many natural foods that contain a large amount of vitamin D. But manufacturers have figured out how to fill its deficit for those who do not eat fish, mushrooms and eggs. Some products are additionally enriched with vitamins. Cow’s milk is a source of many nutrients, including calcium, phosphorus, and Riboflavin. The enriched product contains 115-130 IU of vitamin D per cup (230-250 ml).
Since vitamin D is mainly found in animal products, vegetarians are at high risk of vitamin d deficiency. For this reason, animal milk substitutes are also often additionally enriched with nutrients. Vitamin D is added to soy, oatmeal, buckwheat and other types of vegetable milk. Information about useful additives is indicated on the packaging; read the composition before purchasing.
About 75% of people in the world suffer from varying degrees of lactose intolerance, and 2-3%—from milk allergy. Therefore, you can also find other products in stores that are enriched with nutrients, such as calcium and vitamin D. One glass (250 ml) of orange juice contains about 100 IU, or 12% of the daily value.
Vitamin D and calcium
“Solar vitamin” is necessary for proper absorption of calcium, which plays a key role in strengthening bones and skeletal integrity. Sufficient amounts of both substances reduce the risk of osteoporosis. Children aged one to seven years and adults need approximately 600 IU of vitamin D per day. People over 70 years of age should receive at least 800 IU (20 mcg) of the substance per day. The need for calcium also depends on age: children from one to eight years old need about 2500 mg per day, from nine to 18 years—3000 mg. Adults from 19 to 50 years require 2500 mg per day, and after 50—2000 mg.
Add high-calcium foods to your diet, such as cheese, Greek yogurt, spinach, Kale salad, and soy. Some foods contain both calcium and vitamin D, such as salmon, sardines, and fortified orange juice.
How to take vitamins correctly and why it is necessary
Vitamin D is a fat-soluble vitamin that is involved in the regulation of calcium-phosphorus metabolism and the maintenance of immunity, antitumor protection and many other body functions. Vitamin D is synthesized in the skin under the influence of UV rays, and also comes with food. But to turn it into an active form, it goes through two more stages of activation in the body: in the liver and kidneys.
To make up for the vitamin d deficiency, food alone is not enough, since its content in most products is extremely low. The leader in vitamin D content is fish: for example, wild salmon contains 600-1000 IU per 100 g, herring—up to 1676 IU, sardines—300-600 IU, canned tuna—236 IU. Other foods contain vitamin D in negligible amounts: sour cream—50 IU per 100 g, butter—52 IU, egg yolk—20 IU per piece, beef liver—45 IU per 100 g, milk-only 2 IU per 100 g of the product.
To prevent vitamin D deficiency, an adult is recommended to receive at least 600-800 IU per day, and in case of insufficiency—at least 1500-2000 IU.
The situation may be aggravated by impaired absorption of vitamin D from food in diseases of the gastrointestinal tract, obesity and diabetes. Then a significantly higher dose of native vitamin d may be required to correct the deficiency. Of course, it is impossible to get high doses of vitamin D with food alone. Therefore, to fill the deficit, we recommend native vitamin D (colecalciferol), the dose of which is selected individually by an endocrinologist.