Who Is Most at Risk of Nutritional Deficiency? Identifying Vulnerable Populations

October 5, 2025 •

4 min read

According to the World Health Organization, micronutrient deficiencies are a major public health concern globally, disproportionately affecting pregnant women, lactating women, and young children. Understanding who is most at risk of nutritional deficiency is the first step towards prevention and intervention for these vulnerable groups.

Quick Summary

Certain demographics face a higher risk of malnutrition due to increased needs or impaired nutrient absorption. These include infants, children, pregnant women, older adults, and people with chronic health conditions or restrictive eating habits.

Key Points

Children & Infants: Rapid growth makes them highly susceptible to deficiencies in iron, vitamin D, and vitamin A, which can impact development.
Pregnant & Lactating Women: Increased nutrient demands place them at risk for iron-deficiency anemia and folic acid deficiency, which can harm both mother and child.
Older Adults: Age-related changes in appetite, absorption, and mobility increase the risk of deficiencies, particularly vitamin B12.
Chronic Illness Patients: Malabsorption due to conditions like IBD, as well as the effects of disease and medication, can lead to chronic nutritional issues.
Restrictive Diets: Careful planning is essential for those on vegan or other restrictive diets to prevent deficiencies in key nutrients like B12, iron, and zinc.
Poverty and Access: Low-income and geographically isolated populations have less access to nutrient-rich foods, leading to higher rates of deficiency.

Understanding Nutritional Deficiency

Nutritional deficiency, or malnutrition, occurs when the body does not get enough of the essential vitamins, minerals, and other nutrients it needs to function properly. It is not limited to those in developing countries; it is a significant concern even in resource-rich nations due to various socioeconomic, lifestyle, and health-related factors. While a balanced diet is the cornerstone of good health, certain life stages and health conditions elevate the risk, making specific groups particularly vulnerable.

Infants, Children, and Adolescents

Rapid growth and development in the early years place children at a high risk for nutritional deficiencies, as their bodies require a concentrated intake of specific nutrients. For example, iron deficiency is a major concern for young children and adolescent girls, often leading to anemia with effects on cognitive and motor development.

Common Deficiencies in Children:

Iron: Crucial for brain development and red blood cell production.
Vitamin D: Essential for bone growth and development, especially in infants.
Vitamin A: Important for vision and immune function.
Iodine: Critical for proper thyroid function and cognitive development.

Pregnant and Lactating Women

The nutritional needs of women increase dramatically during pregnancy and breastfeeding to support both their own health and the development of their baby. Deficiencies during this period can have severe consequences, including increased risk of complications during childbirth and developmental issues for the infant.

Key Risks for Pregnant and Lactating Women:

Anemia: Affects a large percentage of pregnant women worldwide and is often caused by iron deficiency.
Folic Acid Deficiency: Can lead to neural tube defects in the baby.
Iodine Deficiency: Can impair fetal brain development.

Older Adults

Age-related changes, including reduced appetite, difficulty chewing or swallowing (dysphagia), decreased mobility, and financial constraints, make older adults a high-risk group. Additionally, the body's ability to absorb certain nutrients, such as Vitamin B12, can decline with age.

Factors Increasing Risk in the Elderly:

Changes in taste and smell
Social isolation and reduced cooking
Chronic health conditions and polypharmacy (use of multiple medications)

Individuals with Chronic Health Conditions

Many chronic diseases directly impact nutrient absorption, appetite, and the body's metabolic processes. Conditions like Crohn's disease, celiac disease, and other inflammatory bowel diseases can lead to malabsorption, regardless of a person's diet.

Conditions Linked to Increased Deficiency Risk:

Gastrointestinal Disorders: Inflammatory bowel diseases (IBD) and celiac disease.
Renal Disease: Chronic kidney disease can alter nutrient metabolism.
Cancer and HIV: These diseases and their treatments can severely impact appetite and nutrient utilization.

People on Restrictive Diets

Whether by choice (e.g., vegetarian, vegan) or necessity (e.g., food allergies), restrictive diets require careful planning to avoid deficiencies. While well-planned versions of these diets can be healthy, poorly managed ones can lead to insufficient intake of crucial nutrients.

Potential Deficiencies with Restrictive Diets:

Vitamin B12: Primarily found in animal products, so vegans are at risk.
Iron, Zinc, and Calcium: Can be lower in plant-based diets.
Omega-3 Fatty Acids: Important for brain health, often from fish.

Nutritional Deficiency Risk Factors Comparison


Risk Factor	Children & Adolescents	Pregnant & Lactating Women	Older Adults	Chronic Illness Patients
Increased Nutrient Needs	High demand due to growth and development.	High demand to support fetal and infant development.	Decreased energy needs, but nutrient density is crucial.	Varies by disease; some increase energy demands or inflammation.
Decreased Absorption	Generally high, unless an underlying condition is present.	Good absorption, but needs exceed intake for some nutrients.	Reduced absorption due to age or medication.	Often impaired by underlying digestive or metabolic conditions.
Socioeconomic Influence	Disadvantaged children are at higher risk.	Low-income countries bear a significant burden.	Income and mobility affect food access.	Financial strain from healthcare costs can impact diet.
Behavioral/Social Factors	Picky eating habits are common.	Dietary restrictions or morning sickness can interfere.	Social isolation, dementia, and reduced mobility are risk factors.	Mental health issues like depression can impact appetite.

Conclusion

While a variety of factors influence an individual's nutritional status, certain populations consistently face a higher risk of deficiency. Infants, growing children, pregnant and lactating women, older adults, and those with chronic diseases or restrictive diets all have unique vulnerabilities that necessitate special attention to their nutritional intake. Addressing these risks requires a multi-faceted approach, including better education, improved food access, and close medical supervision for those with health conditions. By focusing on these at-risk groups, health outcomes can be significantly improved. For more detailed information on specific deficiencies, consult the World Health Organization website. Proper identification and management of nutritional deficiencies are critical steps toward ensuring better health and quality of life for everyone.

Frequently Asked Questions

Infants are at high risk due to their rapid growth and development, which require a much higher density of essential nutrients compared to adults. Deficiencies during this critical period can have long-lasting effects.

Chronic illnesses can affect appetite, impair nutrient absorption, and alter metabolism. Conditions like inflammatory bowel disease (IBD) or cancer are common examples that heighten the risk of malnutrition.

During pregnancy and lactation, a woman's body requires a significantly higher intake of vitamins and minerals to support both her own health and the development of her fetus or nursing infant. This increased demand makes deficiencies, such as iron-deficiency anemia, more likely.

Vegans, who exclude all animal products, are at a higher risk of Vitamin B12 deficiency. Since B12 is found almost exclusively in animal-based foods, supplementation or fortified foods are necessary.

General signs of nutritional deficiency include unexplained weight loss, chronic fatigue, a lack of interest in eating, and frequent illness or a slow recovery time. In children, it may manifest as a failure to grow at the expected rate.

Prevention in older adults involves addressing factors like reduced appetite, medication side effects, and mobility issues. Encouraging nutrient-dense foods, ensuring proper dental care, and promoting social activities can help.

Poverty is a significant contributing factor to nutritional deficiency. Individuals with low income often have limited access to a variety of nutrient-rich foods, making it difficult to maintain a balanced and healthy diet.