Malnutrition And Nutrient Deficiency: What You Need To Know

Nutrient deficiencies are sometimes referred to as “hidden hunger” because they can occur when nutrient requirements aren’t met by an individual’s regular diet. (16)(23) Many factors can contribute to the development of nutrient deficiencies, including impaired digestion, certain medications, (1) and poor dietary patterns. (16)

Various forms of malnutrition, including nutrient deficiencies, have been associated with adverse health symptoms and chronic conditions such as cardiovascular diseases. On the other hand, a healthy diet and supplementation may help to prevent disease and improve quality of life. (16) In this article, you’ll learn about malnutrition, malnutrition symptoms, and what you can do to prevent nutrient deficiencies.

Malnutrition definitions

There are several different terms that relate to malnutrition and nutrient deficiencies, which are defined below.

Malnutrition

Malnutrition is an umbrella term that refers to any form of poor nutrition, including undernutrition (i.e., nutrient deficiencies), overweight, and obesity. (16)(22) The risk of malnutrition is greater in certain populations, including:

• Infants
• Young children
• Pregnant women
• Elderly individuals
• Individuals who have obesity (19)

Undernutrition

Undernutrition refers to any nutrient deficiency and is associated with poor health outcomes such as child stunting, child wasting, and maternal underweight, a factor that increases the risk of complications during pregnancy. Undernutrition is typically viewed as occurring only in countries or communities that experience famine or food insecurity; however, it is also associated with malabsorptive disorders and poor-quality diets, which can occur anywhere in the world. (22)

Nutrient deficiencies can involve an inadequate supply of calories (i.e., energy), certain macronutrients (e.g., protein), or certain micronutrients (e.g., vitamin C). Multiple nutrient deficiencies commonly occur and can make resolving malnutrition more challenging. (22)

Chronic and severe nutrient deficiencies can result in certain deficiency-related diseases, such as beriberi (from thiamine (vitamin B1) deficiency), scurvy (from vitamin C deficiency), and anemia (from iron and B vitamin deficiencies). (17)  

Not only caused by low nutrient intake, nutrient deficiencies can also result from malabsorption. (22)

Micronutrient deficiency

Micronutrient deficiency is characterized by a lack of vitamins and/or minerals and is associated with various symptoms. When referring to particular micronutrients, the terms vitamin deficiency or mineral deficiency are often used. Micronutrient deficiencies are commonly seen in individuals who are underweight, have inadequate energy intake (i.e., too few calories), and have obesity. (22)

Did you know? The NHANES 2007-2010 survey identified that approximately 94.3% of American adults don’t meet the daily requirement for vitamin D, 88.5% for vitamin E, 52.2% for magnesium, 44.1% for calcium, 43% for vitamin A, and 38.9% for vitamin C. (11)

Nutrient insufficiency

Nutrient insufficiency, also called nutrient inadequacy, is a state between normal nutritional status and nutrient deficiency. (17) Nutrient inadequacies are difficult to detect, as they generally do not cause obvious symptoms. (11) However, both nutrient insufficiency and deficiency may lead to dysfunction and disease, making it important to prevent these conditions with adequate nutrition. (10)

Toxicity

Toxicity refers to the degree to which a substance is harmful or poisonous. (13) Toxicity is a type of malnutrition that can occur with overconsumption of a specific substance. In some cases, such as excessive supplementation, an ingredient or ingredients may build up in the body to a harmful level, resulting in adverse effects. For example, acute high doses of iron supplements have been associated with abdominal pain, vomiting, constipation, faintness, and reduced zinc absorption. (14)

Signs of malnutrition

Malnutrition symptoms can range depending on the nutrient that is deficient and the severity of the deficiency. Also, different signs and symptoms may occur depending on an individual’s life stage. (16)(19) Nutrient deficiencies are measured in various ways, such as using diagnostic tests (e.g., blood, serum, and urine tests) and assessing dietary intake and malnutrition symptoms. (22) Several signs of malnutrition are outlined below.

Impaired development in infancy and early childhood

Undernutrition in the womb and during infancy can impair a baby’s physical and cognitive development. For infant growth and development, certain nutrients must be provided from the pregnant or breastfeeding mother’s diet, such as B vitamins, vitamins A and D, iodine, selenium, and polyunsaturated fatty acid (PUFAs). (19)

Complications during pregnancy

Certain nutrient deficiencies may contribute to pregnancy complications, with adverse outcomes affecting both the mother and child. Calcium insufficiency and vitamin D deficiency have been associated with an increased risk of preterm birth, high blood pressure during pregnancy, and the development of other health conditions in the mother. (15)

Fatigue in the general population

Physical fatigue and lethargy are commonly reported symptoms of nutrient deficiencies and insufficiencies. Inadequate intakes of nutrients such as magnesium, iron, B vitamins, and vitamin C have been associated with both mental and physical fatigue. (17)

Muscle pain and cramping

Certain nutrient deficiencies, such as magnesium, thiamine, and vitamin C deficiencies, can affect muscle function and may lead to muscle pain or weakness. (17)

Decreased immune function

Many nutrients help support immune function, such as vitamin A, vitamin D, and zinc. According to the Centers for Disease Control and Prevention, deficiencies in these nutrients may increase the risk of disease from bacterial and viral infections, such as diarrhea, pneumonia, and measles. (2)

Cognitive decline in the elderly

Research has found that low levels of vitamin D may increase the risk of dementia. There is also some evidence suggesting that higher serum levels of vitamins A, C, and E are associated with a reduced risk of Alzheimer’s disease and mild cognitive impairment. (19)

Did you know? Vitamin D, produced by the skin with sunlight exposure, is the only micronutrient produced by the body. However, the amount of sunlight exposure and vitamin D synthesis varies based on factors such as season, geography, and skin color, and vitamin D deficiency is common worldwide. (2)

Consuming a nutrient-dense diet at any age can help prevent nutrient deficiencies. (19)(20)

Preventing nutrient deficiency

Follow the tips below to help optimize your dietary intake and prevent nutrient deficiencies.

Understand what the recommended daily intakes mean

In the United States and Canada, there are several terms that have been historically used to describe nutrient reference values for dietary intake, including Recommended Dietary Allowances (RDAs) and Recommended Nutrient Intakes (RNIs). These refer to the average daily intake of a nutrient needed to meet the requirement of 97 to 98% of healthy individuals. (7)(18)

The Institute of Medicine has since expanded the RDAs and RNIs to the Dietary Reference Intakes (DRIs). DRIs, now the standard used in both countries, incorporate various nutrient reference values, which are outlined in the following table.  

When looking at Dietary Reference Intakes, you’ll see different nutrient reference values used depending on the particular nutrient. (7)(18)

Identify your recommended daily intakes

The Dietary Guidelines for Americans specifies DRIs for age-sex groups. (20) Similarly, Health Canada provides Dietary Reference Intakes tables, which specify DRIs for macronutrients, vitamins, and minerals by population. (6) You can use these resources to determine your individual daily intake goals.

Read food labels

Nutrition facts labels on food identify the amounts of calories and nutrients contained in a serving of the food or beverage. The “% daily value” column on the label can help you identify foods that are a high source of nutrients. “5% daily value” or less of a nutrient per serving is considered low. In the United States, 20% or more is considered high, while on Canadian food labels, 15% daily value or more is considered high. (8)(21)

The U.S. Food and Drug Administration’s (FDA) new Nutrition Facts label requires amounts of vitamin D, calcium, iron, and potassium to be listed on food labels. Research shows that intake of these micronutrients is generally low and deficiencies are common in the American population. These nutrient deficiencies have been associated with an increased risk of health conditions including anemia, high blood pressure, and osteoporosis. (21)

Health Canada currently requires the micronutrients potassium, calcium, and iron to be listed on the Nutrition facts label as the intake of these minerals has been identified as generally low in the Canadian population. (9)

Use a diet tracking app

Diet tracking apps are a helpful tool that you can use to record your dietary consumption and assess your intake of specific nutrients. Examples of wellness apps for diet tracking include:

• Cronometer
• Lose It!
• MyFitnessPal
• MyMacros+
• MyPlate

Consume a nutrient-dense diet

Scientific literature and current nutrition guidelines recommend consuming a nutrient-dense diet to meet nutrient needs and reduce the risk of obesity and chronic diseases. (19)(20) While there is no strict definition of a nutrient-dense diet, it generally involves consuming a variety of foods with a high ratio of essential nutrients to energy. (19)

Increasing the nutrient density of your diet involves avoiding energy-dense, nutrient-poor foods, sometimes referred to as “empty calories”, such as:

• Added sugars (e.g., baked goods, candy, cereals, desserts)
• Foods with added fats (e.g., fried foods, takeout meals)
• Sugar-sweetened beverages (e.g., sweetened juice, soda, energy drinks) (19)

An overall nutrient-dense dietary pattern includes whole foods, preferably foods that are local, fresh, organic, and unprocessed. (16) Examples of nutrient-dense foods to increase in your diet include:

• Animal proteins (e.g., eggs, lean meats, fish, seafood, organ meats)
• Fruits and vegetables
• Natural dairy products (i.e., unsweetened and minimally processed)
• Nuts and seeds
• Whole grains (16)(19)

Download a handout on the foundations of a healthy diet.

Supplement your diet

When it comes to meeting your nutrient needs, a healthy diet always comes first. In some cases, there is strong evidence supporting the use of dietary supplements in addition to a healthy diet. For instance, folate supplements are recommended for pregnant women and women who could become pregnant, as supplemental intake of this nutrient has been shown to reduce the risk of neural tube defects in the baby. (7)

In other cases, supplements may be used to address existing nutrient deficiencies or prevent nutrient deficiencies in individuals who are at risk. Factors that may affect an individual’s nutrient status and supplementation needs include:

• A decline of nutrient levels in foods associated with modern agricultural practices (4)
• Increased nutrient requirements (e.g., during adolescence, pregnancy, lactation, athletic performance) (1)
• A poor quality diet (e.g., the Standard American Diet (SAD)) (5)
• Impaired digestion and nutrient absorption
• Increased metabolic nutrient loss (e.g., critical illness, aging) (1)
• Low dietary intake and/or eliminating certain foods or food groups (e.g., calorie restriction, (5) vegan diet) (3)
• Nutrient-depleting effects of certain medications (e.g., diuretics, oral contraceptives, proton-pump inhibitors, statins) (12)

Your integrative practitioner can help identify nutrient deficiencies and underlying contributing factors as well as determine the best supplement(s) for your individual needs.

Caution: To avoid toxicity, drug-nutrient interactions, and other health concerns, it’s important to have proper diagnostic testing performed by your practitioner to determine if you have a nutrient deficiency. Always consult your integrative practitioner before introducing new supplements to your regimen.

The bottom line

Staying informed about recommended nutrient intakes can help ensure you meet your requirements for optimal health. Prioritize consuming a diverse, nutrient-dense diet, and work with your integrative practitioner to identify nutrient deficiencies and develop a treatment plan.