Any nutritional deficiency can have different causes but basic cause of nutritional deficiency includes inadequate intake, inadequate absorption and increased requirement of a nutrient which is not met.
- When diet is inadequate in vitamins or minerals – Following a restricted diet or fad diet which generally lacks in important vitamins and minerals such as vitamin B, vitamin C, zinc and iron can lead to a deficiency. Eating unhealthy or unbalanced diet or eating too much of processed and junk food also lacks in essential vitamins and minerals because processing of food can leach out vitamins and minerals.
- Being vegetarian or vegan can lead to protein deficiency – Vegetarians who don’t eat dairy products and are vegans, who don’t eat any foods from animals are generally protein and calcium deficient because dairy products are good source of calcium as well as protein.
- Vitamin deficiency & cooking – Consistently overcooking your food also can cause vitamin deficiency. Overcooking of food destroys vitamins from the food.
- Special times when the requirement is high – There are times when you require more nutrients than usual for example in pregnancy the need of protein, iron and folic acid is high. Nutritional deficiency occurs if the diet lacks the proper amount of these nutrients.
- If there is an intestinal problem or other medical conditions that interfere with absorption of vitamins – Abnormal bacterial growth in your stomach or surgery to your intestines or stomach can interfere with the absorption of vitamin B-12, leading to a deficiency.
- Alcohol & deficiency – Consumption of alcohol interferes with the absorption of folate and vitamin C, as well as other vitamins.
- Drugs causing deficiency – There are certain prescription medications that can block absorption of vitamins. Anti-seizure drugs can block the absorption of vitamins. Antacids and some drugs used to treat type 2 diabetes may interfere with B-12 absorption.
- Smoking – Smoking also leads to vitamin C deficiency because it decreases the absorption of this vitamin.