What Happens If Your Subcutaneous Fat Is Low?

Research indicates that the immune system is often impaired when body fat stores, including subcutaneous fat, are too low, increasing the body's susceptibility to infections. What happens if your subcutaneous fat is low is not merely a cosmetic concern, but a significant health issue affecting numerous bodily systems and functions.

Quick Summary

Insufficient subcutaneous fat impairs vital bodily functions, causing problems with immunity, hormonal balance, temperature regulation, and nutrient absorption. The health risks intensify when body fat drops below essential levels.

Key Points

• Poor Insulation: Low subcutaneous fat leads to impaired temperature regulation, making one more susceptible to feeling cold.

• Weakened Immunity: Insufficient fat stores can suppress the immune system, increasing vulnerability to infections and illnesses.

• Hormonal Disruption: Low body fat can cause hormonal imbalances, such as decreased estrogen in women, affecting reproductive health and bone density.

• Fat-Soluble Vitamin Issues: Adequate fat is necessary for absorbing vitamins A, D, E, and K, meaning deficiency is a risk.

• Fatigue and Low Energy: Subcutaneous fat is an energy reserve, and low levels can result in reduced energy and chronic fatigue.

• Metabolic Problems: In cases like lipodystrophy, low subcutaneous fat can cause improper fat storage elsewhere, leading to metabolic issues.

• Protective Role: Some studies suggest subcutaneous fat can offer a protective effect against the more dangerous visceral fat.

The Vital Functions of Subcutaneous Fat

Subcutaneous fat is the layer of adipose tissue located just beneath the skin, the kind you can pinch. It plays several crucial roles for your body's overall health and functioning. Primarily, it acts as a thermal insulator, helping to regulate body temperature and protect against cold environments. It also serves as an energy reserve, storing calories that the body can draw upon for fuel during periods of low food intake. Furthermore, subcutaneous fat acts as a protective cushion, shielding your organs, bones, and muscles from physical impact and injury. Unlike visceral fat, which surrounds the internal organs and is considered more dangerous, subcutaneous fat can even offer a protective effect against some metabolic risks associated with high visceral fat.

Health Complications from Low Subcutaneous Fat

When subcutaneous fat levels drop below a healthy minimum—often considered less than 5% for men and 15% for women—several significant health problems can arise. These issues stem from the body's inability to perform the fat's vital functions and can impact multiple physiological systems.

Impaired Immune Function

One of the most concerning effects is a weakened immune system. Fat cells, or adipocytes, play a role in regulating immune responses. When fat stores are too low, the immune system's ability to fight off infections can be compromised, leading to more frequent and prolonged illnesses. This can significantly interrupt training for athletes and diminish overall well-being.

Poor Body Temperature Regulation

Subcutaneous fat is a powerful insulator. With low levels, the body loses heat more easily, making individuals highly sensitive to cold temperatures. Newborns, for example, have underdeveloped subcutaneous fat layers, which is why they are more susceptible to hypothermia. Adults with low subcutaneous fat may experience a constant cold sensation, even in mild conditions, as their bodies struggle to maintain core temperature.

Hormonal Imbalances

Fat tissue is an endocrine organ that produces hormones essential for regulating various bodily functions. A severe lack of body fat, especially in women, can lead to a drop in circulating estrogen levels. This can cause amenorrhea (loss of menstruation) and, over time, a loss of bone mass, increasing the risk of osteoporosis later in life. Additionally, levels of leptin, a hormone that regulates hunger, can decrease. This can disrupt appetite signals and affect metabolism.

Risk of Vitamin Deficiencies

Four essential vitamins—A, D, E, and K—are fat-soluble, meaning they require dietary fat for proper absorption and transport. With insufficient body fat and potentially reduced fat intake, the body's ability to absorb these crucial nutrients is compromised. Deficiencies in these vitamins can lead to a host of problems, from impaired vision (Vitamin A) and weakened bones (Vitamin D) to issues with blood clotting (Vitamin K) and antioxidant protection (Vitamin E).

Potential Metabolic Issues

Research shows a link between low subcutaneous thigh fat and unfavorable glucose and lipid levels, even independently of high abdominal fat. In conditions like lipodystrophy, where subcutaneous fat is lost, fat can be improperly stored in other tissues like the liver, pancreas, and muscles. This can lead to serious metabolic conditions, including insulin resistance, fatty liver disease, high triglycerides, and diabetes.

Low Subcutaneous Fat vs. Visceral Fat

While both types of fat are part of overall body composition, their location and metabolic activity differ significantly, leading to distinct health impacts. It is crucial to understand this difference, as some people can have low subcutaneous fat but still have high, dangerous visceral fat levels.

Feature	Subcutaneous Fat	Visceral Fat
Location	Just beneath the skin.	Deep inside the abdominal cavity, surrounding organs.
Appearance	Visible; pinchable layer.	Not visible; 'intra-abdominal fat'.
Health Impact	Generally less harmful, but low levels cause specific risks.	More metabolically active and dangerous, linked to inflammation and metabolic disease.
Metabolic Activity	Less metabolically active.	Highly metabolically active, releasing inflammatory cytokines.
Primary Function	Insulation, energy storage, cushioning.	Some studies suggest storage may protect against metabolic risks.
Risks of Low Levels	Impaired immunity, poor insulation, hormonal disruption.	N/A (high visceral fat is the risk).

How to Address Insufficient Subcutaneous Fat

For individuals with a naturally low body fat percentage, or those recovering from significant weight loss, increasing subcutaneous fat should be done safely and healthily. The goal is a balanced body composition, not just adding any type of fat. Medical supervision is recommended, particularly for athletes or those with underlying health conditions.

Here are some strategies:

• Create a Calorie Surplus: Consume more calories than you burn daily to gain weight gradually. Online calculators can help estimate your daily energy expenditure.
• Focus on Nutrient-Dense Foods: Choose foods rich in healthy fats, proteins, and carbohydrates. This ensures your body receives essential nutrients, not just empty calories.
  • Nuts and seeds (almonds, walnuts, chia seeds)
  • Avocado and olive oil
  • Whole grains and potatoes
  • Lean proteins (fish, chicken, eggs)
  • Full-fat dairy products if tolerated
• Incorporate Healthy Fats: Don't fear fats. Healthy sources like avocados, nuts, seeds, and olive oil are key for energy and fat-soluble vitamin absorption.
• Boost Protein Intake: Protein intake is crucial for supporting muscle growth alongside fat gain. Good sources include fish, eggs, dairy, and legumes.
• Engage in Strength Training: Resistance training helps ensure that weight gain is a healthy mix of fat and muscle, rather than just fat. This also helps improve muscle density, which can contribute to overall weight in a healthy way.
• Prioritize Sleep and Stress Management: Both sleep deprivation and high stress levels can disrupt hormones that regulate appetite and fat storage. Aim for 7-9 hours of quality sleep per night and manage stress through relaxation techniques.
• Consider Professional Guidance: For significant underweight or health issues related to low body fat, consulting a doctor, registered dietitian, or nutritionist is the safest approach. They can provide a personalized plan tailored to your specific needs.

Conclusion

While a low body fat percentage is often associated with peak fitness, having too little subcutaneous fat can pose serious health risks. From compromising the immune system and impairing temperature regulation to causing hormonal imbalances and fat-soluble vitamin deficiencies, the consequences underscore the importance of maintaining a healthy and balanced body composition. Subcutaneous fat is a vital component of the body's protective and metabolic systems, and understanding its functions is key to appreciating the potential harm of extremely low levels. If you suspect your subcutaneous fat levels are too low, seeking professional medical advice is the most prudent step toward restoring health and well-being. Subcutaneous Fat - Cleveland Clinic

Comparison: Subcutaneous vs. Visceral Fat

Feature	Subcutaneous Fat	Visceral Fat
Location	Just beneath the skin, visible and pinchable.	Deep inside the abdominal cavity, surrounding internal organs.
Appearance	Visible fat layer, often on thighs, hips, and stomach.	Invisible from the outside, located deep within the torso.
Health Implications	Less metabolically active, generally less harmful, but low levels pose specific risks.	Highly metabolically active, releases inflammatory substances, and strongly linked to heart disease and diabetes.
Function	Insulation, energy storage, protective cushion.	Metabolically active fat, can influence hormonal balance and inflammation.
Risks of Deficiency	Impaired immunity, poor insulation, hormonal disruption, vitamin deficiencies.	High levels are the risk, not low levels.

Addressing Insufficient Subcutaneous Fat: A List of Healthy Strategies

• Increase overall caloric intake through nutrient-dense foods.
• Focus on healthy fats from sources like avocados, nuts, and olive oil.
• Ensure adequate protein intake to support muscle growth alongside fat gain.
• Engage in regular strength training to build muscle mass.
• Prioritize sufficient sleep to support hormone balance.
• Practice stress reduction techniques to regulate cortisol levels.
• Consult a healthcare professional for personalized guidance.

Frequently Asked Questions

Can low subcutaneous fat cause me to feel cold all the time?

Yes, a primary function of subcutaneous fat is to provide insulation. When levels are low, your body has a harder time regulating temperature, leading to feeling colder, even in mild conditions.

Is low subcutaneous fat the same as low total body fat?

Low subcutaneous fat is a component of low overall body fat, though it's possible to have low subcutaneous fat and still have unhealthy levels of visceral fat. The most severe health risks occur when total body fat drops below essential levels.

What is the risk for vitamin deficiency with low body fat?

There is an increased risk for deficiencies in fat-soluble vitamins (A, D, E, K), as these require dietary fat for proper absorption by the body.

How does low body fat affect the immune system?

When body fat is too low, the immune system can become impaired, reducing the body's ability to fight infections and potentially increasing the frequency of illness.

Can low subcutaneous fat cause hormonal problems?

Yes, especially in women, it can lead to decreased estrogen levels, which can affect menstrual cycles and bone mineral density. Low leptin levels can also impact metabolism.

How can I safely increase my subcutaneous fat?

To increase body fat, you must consume more calories than you burn. Focus on a balanced diet with healthy fats, carbohydrates, and proteins, and consider strength training to build muscle alongside fat.

What are the differences between subcutaneous and visceral fat?

Subcutaneous fat is the visible fat just under the skin, while visceral fat is located deep around the organs. Visceral fat is generally considered more metabolically harmful, but low subcutaneous fat has its own set of health consequences.