Hidden Fat: The Impact of Intramuscular Fat on Health and Longevity

When considering the top causes of death, smoking, cancer, and obesity often come to mind. However, there is a hidden danger lurking within our bodies that is often overlooked by many, including medical professionals.

“It’s not just about the amount of muscle, but the quality and composition that truly impact how adults function,” she explained.

Intramuscular fat, also known as myosteatosis, significantly impacts muscle quality. Unlike subcutaneous fat (stored under the skin) or visceral fat (around organs), intramuscular fat infiltrates muscle fibers, leading to a decline in their performance and functionality. It can accumulate between muscle fibers or within muscle cells.

Dr. Sean O’Mara, a renowned expert in reversing chronic illnesses, describes myosteatosis as “fat replacing your muscle” or “human marbling.” In a discussion with The Epoch Times, he elaborated on how this process can degrade muscle mass and performance, resulting in various health issues.

“We have learned that even if you have the same amount of muscle, having more fat within those muscles means they do not function as effectively,” Addison added.

The Dangers of Intramuscular Fat

Muscles with higher fat content are less efficient, leading to a reduction in strength and mobility, especially as individuals age. However, myosteatosis poses significant health risks beyond impaired muscle functionality.

Out of the 507 participants who passed away, 55 percent had myosteatosis, resulting in a 16 percent chance of dying within 10 years—a higher risk than obesity, fatty liver disease, and muscle wasting.

“If you have this fat in your muscle, then you have double the risk of mortality compared to an obese individual,” O’Mara emphasized, highlighting the deadly potential of myosteatosis.

Similar to visceral fat, intramuscular fat releases harmful inflammatory molecules.

“This fat within the muscle behaves similarly to how visceral fat in your abdomen acts, being highly inflammatory,” Addison noted.

JJ Virgin, a fitness and nutrition expert, informed The Epoch Times that intramuscular fat “releases pro-inflammatory cytokines, causing systemic inflammation.”

Virgin explained, “Muscles are where we dispose of our glucose. With fatty muscles, you develop metabolic dysfunction, insulin resistance, and impaired glucose disposal.”

Addison stated, “There are metabolic repercussions. Individuals with high levels of this fat in their muscles are more likely to develop diabetes, insulin resistance, and experience poor surgical recovery.”

O’Mara explained that individuals with larger muscles, such as bodybuilders who consume high levels of carbohydrates, tend to have more intramuscular fat, contributing to an increased risk of heart disease. In contrast, those with denser muscles, who consume fewer carbs, naturally have lower levels of intramuscular fat, reducing their risk of heart disease.

“Essentially, you want muscles without fat,” O’Mara concluded.

One immediate concern is the impact of myosteatosis on mobility. “We know for sure that having more of this fat increases the likelihood of a decline in movement and independence over time,” Addison remarked.

This decline can lead to frailty, an increased risk of falls, and a loss of independence, especially among older adults.

However, not all intramuscular fat is detrimental. “Endurance athletes tend to have more marbling in their muscles,” as it serves as an energy source, Virgin pointed out.

Development of Fatty Muscles

Intramuscular fat often accompanies other harmful fat deposits such as visceral fat and deep subcutaneous fat.

“If you have a lot of visceral fat, you likely have a significant amount of muscle fat as well,” O’Mara explained.

Several factors contribute to myosteatosis. Diet plays a crucial role, with a high intake of carbohydrates, particularly processed foods, being a primary contributor.

“Carbohydrates, especially processed foods, all contribute to intramuscular fat. In the absence of carbohydrates, fat and protein have minimal effects on fat accumulation,” O’Mara noted.

Alcohol consumption worsens the condition by hindering the elimination of visceral fat and promoting additional fat deposition. Poor sleep, which is common in individuals with sleep disorders like obstructive sleep apnea, also contributes. Stress is equally harmful.

“Individuals with high stress levels, such as politicians under constant pressure, often exhibit elevated levels of fat,” O’Mara stated.

“The primary factors are inactivity and an increase in body weight,” Virgin emphasized.

Addison explained that age and genetics also play a role, although further research is needed to fully understand their impact.

Identifying Myosteatosis: Tools and Techniques

Addison highlighted that there is currently no standardized method for measuring intramuscular fat.

“I believe it is an area where the medical field has not fully caught up yet,” she remarked, pointing out deficiencies in current practices.

Despite advancements in imaging technologies such as MRI (magnetic resonance imaging) and CT (computed tomography) scans, intramuscular fat is not routinely measured outside of research environments.

However, some healthcare providers, like O’Mara, do measure various types of fat in the body. According to O’Mara, MRI is the preferred method for detecting myosteatosis due to its superior imaging capabilities, which allow for detailed images that differentiate between healthy muscle tissue and fat infiltration.

“Muscle appears dark, while fat appears white on an MRI. When white infiltrates dark muscle, that indicates fat replacing muscle, significantly impacting muscle performance,” O’Mara explained.

Although MRIs are typically more costly, broader utilization could lead to reduced costs and improved health outcomes by enhancing diagnostic accuracy and early detection, he noted.

Visual feedback from an MRI can be valuable for patient education and engagement, O’Mara emphasized. He stressed the importance of showing patients images of their muscles compared to healthy and unhealthy tissue.

“When discussing muscle fat, telling someone they have ‘6% fat in their muscles’ is not as effective,” he stated.

“However, showing them their muscles and the fat, alongside images of what is considered good and bad, creates a more powerful and impactful experience than just providing numeric scores,” he added.

This visual approach motivates patients to make necessary lifestyle changes more effectively than numerical data alone.

CT scans offer a more cost-effective alternative to MRIs while still providing valuable information on muscle fat content. Although less detailed than MRIs, CT scans are widely utilized due to their accessibility. However, O’Mara cautioned about the radiation risk associated with CT scans.

Virgin agreed that “MRI is the best method for higher sensitivity in detecting fat in the muscle.” She also mentioned that DEXA scans are the “next best option in terms of ease of use and cost” and closely correlate with MRI. DEXA scans (dual-energy X-ray absorptiometry) utilize low-dose X-rays to measure bone density and body composition, including fat and muscle mass.

Dr. Sandeep Palakodeti, chief medical officer of Rebel Health Alliance, acknowledged that DEXA scans offer insights into overall body fat, including subcutaneous and visceral fat, but cautioned in an interview with The Epoch Times, “I do not believe they can adequately differentiate intramuscular fat from other types of fat as effectively as MRI or CT scans.”

Ultrasound is emerging as a practical and non-invasive method for measuring muscle fat.

Addison highlighted the work of Dr. Michael Harris-Love from the University of Colorado, stating, “Ultrasound is much more accessible in clinical settings. We are developing techniques to assess muscle fat content using ultrasound, allowing for a quick, non-invasive evaluation during routine appointments.”

Prevention and Management Strategies

Preventing and managing intramuscular fat involves lifestyle modifications and targeted approaches to enhance overall muscle health.

“I always stress that prevention is better than treatment. However, when it comes to treatment currently, our best options are diet and exercise combined,” Addison emphasized.

O’Mara also highlighted the importance of diet, exercise, and sleep.

“Carbohydrates, especially processed foods, all contribute to visceral fat,” he stated, emphasizing the need to reduce these in favor of healthier options like protein and healthy fats. He also recommended limiting alcohol intake and ensuring adequate sleep to prevent fat accumulation.

“The focus should be on the quality of the muscle,” Addison emphasized, encouraging individuals to engage in exercises that improve muscle density rather than just increasing muscle size.

Virgin also stressed the importance of maintaining physical activity to prevent the development of fatty muscles, stating, “Obesity combined with low activity levels leads to high levels of fatty muscle.”

“Caloric restriction alone is not as effective as combining it with physical activity. You will see twice the reduction in fatty infiltrate if you do both together rather than just trying to lose weight through diet alone,” she added.

Proper hydration and stress management are also essential. Chronic stress can elevate cortisol levels, promoting fat storage. Techniques such as mindfulness, yoga, and other relaxation methods can help effectively manage stress levels.

By adopting these strategies, individuals can take proactive steps to reduce intramuscular fat, enhance muscle quality, and improve overall health.