Calcium supplements form “Ca” symbol representing important micronutrients in the post op bariatric surgery diet

Micronutrients are critical for our health but compounds that, unlike macronutrients, our body requires in tiny amounts (our needs are often expressed in milligrams or micrograms). The term comes from the Greek word “mikros,” which means small, and the Latin word “nutriens,” which means feed, support, and preserve. They are often referred to as simply “Micros.”

Micronutrients are composed of 2 categories: vitamins and minerals. Vitamins are organic compounds that plants or animals produce. On the other hand, minerals are inorganic substances naturally found in water and soil and absorbed by living plants and animals.

Our body cannot produce vitamins and minerals; consequently, micronutrients are considered “essential” as they must be obtained through food and water. There are a few exceptions, such as vitamin D, a nutrient we get through food or exposure to the sun, and a hormone our body produces.


There are fourteen vitamins that our body requires in sufficient amounts for good health: vitamin A, vitamin B1 (thiamine), vitamin B2 (riboflavin), vitamin B3 (niacin), vitamin B5 (pantothenic acid), vitamin B6 (pyridoxine), vitamin B7 (biotin), vitamin B9 (folic acid or folate), vitamin B12 (cobalamins), vitamin C (ascorbic acid), vitamin D (calciferol), vitamin E (tocopherols and tocotrienols) and vitamin K (phylloquinone and menaquinones).

These vitamins can be divided into two categories: water-soluble and fat-soluble.

Water-soluble vitamins have the characteristic that they dissolve quickly in water and are readily excreted from the body through urine. Our body does not efficiently store these vitamins, so to prevent deficiencies, it is essential to obtain them regularly. The water-soluble vitamins are eight: all the vitamin Bs and vitamin C.

Fat-soluble vitamins are absorbed in the intestinal tract along with dietary fats. These vitamins are stored in the body’s fatty tissues and the liver. Consequently, the body can accumulate some of these vitamins (for example, vitamin A and D), and there is a higher risk of toxicity (hypervitaminosis) for this category of vitamins than for water-soluble vitamins. The fat-soluble vitamins are four: Vitamin A, D, E, and K.


The second category of micronutrients – minerals – can be divided into macrominerals and trace minerals.

Macrominerals are the minerals that our body requires in more significant amounts. These mineral types include sodium, potassium, magnesium, calcium, and chloride. For example, an average healthy adult needs approximately 1,500 mg daily (milligrams) of sodium.

Trace minerals are just as important for our health as macrominerals, but we need to consume them in smaller amounts. These include iron, zinc, iodine, selenium, copper, fluoride, manganese, and chromium. For example, an average healthy adult requires approximately 150 mcg (micrograms) per day of iodine.

Micronutrient Function, Food Sources, and Recommended Daily Intakes

All micronutrients have specific critical functions and are essential for our health. Different types of food and water are important sources for each micronutrient. For this reason, eating a varied and balanced diet rich in healthy foods is essential.

Our body requires each micronutrient in specific amounts to reach and preserve maximal health. If we consume too little or too much of any micronutrient, we can develop a micronutrient deficiency or micronutrient toxicity, respectively. For this reason, knowing the best food sources for each micronutrient and the Recommended Dietary Allowance (RDAs) is helpful based on age, gender, and life stage.

Vitamin and Mineral Deficiencies in Bariatric Patients

All bariatric patients naturally tend toward a deficiency or at least a shortfall of specific vitamins and minerals. Therefore, all patients must take a daily multivitamin, potentially supplement particular vitamins and minerals and periodically do blood work to check for deficiencies. Bariatric patients commonly experience iron, Vitamin B12, and calcium deficiencies.

Patients undergoing combination restrictive and malabsorptive procedures such as a gastric bypass, Duodenal Switch, or SADI Are often at greater risk of micronutrient deficiencies, including B vitamins, vitamin A, vitamin D, and vitamin K.

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