What are the symptoms of lack of fatty acids? A Comprehensive Guide

October 14, 2025 •

3 min read

While severe essential fatty acid deficiency is rare, suboptimal intake is common and can lead to a variety of health issues. Understanding what are the symptoms of lack of fatty acids is crucial for maintaining your overall well-being.

Quick Summary

Essential fatty acid deficiency, though uncommon, can cause a range of physical and cognitive issues. Key indicators include dry, scaly skin, hair changes, fatigue, mood disturbances, and impaired cognitive function, which can be identified through physical signs and confirmed with a fatty acid profile test.

Key Points

Skin and Hair Symptoms: A lack of fatty acids often presents as dry, scaly skin, eczema-like rashes, hair loss (alopecia), and brittle hair and nails due to impaired cell membrane function.
Cognitive and Psychological Impact: Essential fatty acids support brain health, and deficiency can lead to fatigue, poor memory, difficulty concentrating, mood swings, anxiety, and depression.
Inflammatory and Immune Responses: EFAs regulate inflammation, so a deficiency can result in increased infections, poor wound healing, and joint pain, indicating a compromised immune response.
Causes of Deficiency: Common causes include inadequate dietary intake, fat malabsorption disorders (like cystic fibrosis), long-term intravenous feeding without lipid supplementation, or excessively low-fat diets.
Diagnosis and Treatment: Diagnosis is confirmed through a physical exam and blood tests (such as a fatty acid profile). Treatment involves increasing dietary intake of EFA-rich foods, supplements, or, in severe cases, medical intervention.

The Crucial Role of Essential Fatty Acids

Essential fatty acids (EFAs), which include omega-3 and omega-6, are vital polyunsaturated fats that the body cannot produce and must be obtained through diet. They are critical components of cell membranes and support various bodily functions, including skin health, brain and nerve function, and inflammation regulation. Deficiency can result from insufficient intake, malabsorption, or increased metabolic demands.

Symptoms of Essential Fatty Acid Deficiency

A lack of EFAs can manifest in various symptoms across multiple bodily systems, with some overlap between omega-3 and omega-6 deficiencies.

Skin, Hair, and Nail Problems

Observable signs often appear on the skin, hair, and nails due to the role of fatty acids in cell membranes and hydration. Symptoms may include dry, scaly skin, sometimes with red rashes. Increased susceptibility to conditions like eczema or psoriasis has also been noted. Hair may become dry, dull, brittle, and in severe cases, hair loss can occur. Nails might become brittle and peel, and wound healing may be impaired.

Cognitive and Psychological Symptoms

EFAs, especially omega-3s, are important for brain and nervous system health, and deficiencies can affect mental well-being. This can lead to persistent fatigue, mood swings, depression, poor concentration, and memory issues. Sleep disturbances like difficulty settling or disrupted patterns can also occur, along with occasional excessive thirst and frequent urination.

Inflammatory and Immune Issues

EFAs help regulate inflammation, and a deficiency can lead to increased inflammation and a weakened immune system. This can result in more frequent infections, joint pain or stiffness, and heightened allergic reactions.

Other Signs of Deficiency

Other potential symptoms include visual problems such as dry eyes and poor night vision. In infants and children, EFA deficiency can lead to poor growth and development. A lack or imbalance of EFAs can also impact heart health.

Causes of Fatty Acid Deficiency

While uncommon in the general population, EFA deficiency is more prevalent in individuals with specific conditions or dietary habits. Causes include fat malabsorption disorders, long-term intravenous nutrition without adequate lipid support, extremely low-fat diets, bariatric surgery, and increased metabolic needs in infants.

Diagnosis and Treatment

Diagnosis typically involves a clinical assessment and blood tests, such as a fatty acid profile, to measure specific fatty acid levels and the triene:tetraene ratio. Treatment focuses on restoring EFA levels through dietary changes, supplementation, or medical intervention for severe cases or those with malabsorption.

Comparison of Omega-3 and Omega-6 Deficiencies


Feature	Omega-3 Deficiency	Omega-6 Deficiency
Primary Symptoms	Visual problems, neurological issues, joint pain, mood disturbances, cardiovascular concerns	Dry, scaly rashes (dermatitis), impaired skin barrier function, hair loss, poor wound healing
Key Dietary Sources	Oily fish (salmon, mackerel), flaxseed, walnuts, chia seeds	Vegetable oils (soybean, corn, sunflower), seeds, nuts
Inflammatory Impact	Leads to pro-inflammatory state; omega-3s are anti-inflammatory	Can also promote inflammation if not balanced with omega-3s
Biochemical Marker	Decreased plasma DHA; Omega-3 Index can be measured	Decreased plasma linoleic acid; elevated triene:tetraene ratio

Dietary Sources for Essential Fatty Acids

Ensuring a balanced intake of both omega-3 and omega-6 fatty acids is important. Good food sources for omega-3s include fatty fish, flaxseeds, chia seeds, and walnuts. For omega-6s, consider vegetable oils like corn or soybean oil, various nuts and seeds, and animal products like meat and eggs.

Conclusion

Identifying what are the symptoms of lack of fatty acids is crucial for addressing potential deficiencies. While severe cases are rare, insufficient intake is more common and can contribute to various health problems affecting the skin, brain, and immune system. Maintaining a balanced diet rich in both omega-3 and omega-6 sources is the most effective approach for optimal EFA intake and overall health. Individuals experiencing persistent symptoms or those with malabsorption issues should consult a healthcare provider for proper diagnosis and a personalized treatment plan.

Learn more about the benefits of essential fatty acids at the Linus Pauling Institute.

Frequently Asked Questions

Essential fatty acids (EFAs), primarily omega-3 and omega-6, are polyunsaturated fats that the human body cannot produce on its own. They are crucial for building cell membranes, maintaining brain function, and regulating inflammation and immune responses.

Dry, scaly, or flaky skin is a classic sign of EFA deficiency. Other related symptoms might include eczema, hair loss, or brittle nails. However, these can be caused by other conditions, so a comprehensive assessment by a healthcare professional is recommended.

Cognitive and psychological symptoms can include persistent fatigue, poor concentration, memory problems, mood swings, anxiety, depression, and difficulties with sleep.

Good sources of omega-3s include fatty fish (salmon, mackerel), flaxseeds, and walnuts. For omega-6s, consider vegetable oils (soybean, sunflower), seeds, and nuts. A balanced intake of both is important.

Severe EFA deficiency is rare, but suboptimal intake can be common. It is more likely to occur in individuals with specific health conditions like malabsorption disorders, those on long-term intravenous nutrition, or people following very low-fat diets.

Diagnosis is made through a physical examination to check for clinical signs. A blood test to measure plasma levels of fatty acids and determine the triene:tetraene ratio can confirm the deficiency.

Treatment involves increasing the dietary intake of essential fatty acids, either through food or supplements like fish oil. In severe cases, particularly those involving malabsorption, doctors may prescribe intravenous fat emulsions.

Yes, infants and children are particularly vulnerable due to their high metabolic demands for growth. Symptoms can include poor growth (failure to thrive), skin rashes, and hair loss.