The Silent Fat Compound That Crowds Out Bone-Building Cells

A rarely discussed tissue inside your bones affects bone strength and remodeling by crowding out the cells responsible for new growth.

In this article, we'll dive deep into the science of bone marrow fat. You'll learn about this lipid, the role it plays, what happens if levels get too high, and how you can keep it within a healthy range.

All About Bone Marrow Fat

Bone marrow fat (BMF), also called marrow adipose tissue (MAT) is adipose tissue that develops in bone marrow. Bone marrow is a soft, spongy tissue at the core of many bones. This important tissue generates and stores red blood cells. For more than a century, scientists have known that marrow also contains adipose tissue.

There are two major types of bone marrow fat. Constitutive BMF, found in the limbs, remains relatively constant. Regulatory BMF, located in the bones in the core of the body, such as the pelvis and vertebrae, can increase or decrease in response to environmental and behavioral factors.

Studies have found that BMF is distinct from other adipose tissues in the body; however, it has received far less attention than other forms of fat.¹

Synopsis

Bone marrow fat is a form of adipose tissue that develops in bone marrow. The BMF in the limbs maintains a fairly consistent level, but BMF in bones in the core of the body may increase or decrease in response to environmental and behavioral factors.

Bone Marrow Fat And Bone Mineral Density

Bone marrow fat levels fluctuate over the lifespan, and elevated BMF has been linked to health problems and chronic conditions — including osteoporosis.

One study published in the Journal of Magnetic Resonance Imaging concluded that “osteoporosis is associated with increased marrow fat.”² The study included 15 women with normal bone mineral density, 15 with osteopenic BMD, and 20 with osteoporotic BMD. They found that the women with lower BMD had higher levels of bone marrow fat.

A review of previous studies published in The Journal of Clinical Endocrinology & Metabolism found a negative relationship between BMD and BMF in both healthy and osteoporotic populations. The authors concluded that “most human data demonstrate an inverse relationship between BMF and BMD (bone mineral density).”³

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The authors hoped to examine the link between BMF and fractures, but there was insufficient research documenting fractures in relation to BMF levels.

Synopsis

Studies have found an inverse relationship between bone marrow fat and bone mineral density– higher BMF correlates with lower BMD, and vice versa. This was true for participants with normal BMD and for those with osteoporosis and osteopenia.

Why Bone Marrow Fat Impacts Bone Mineral Density

We don't yet have definitive answers as to why increased bone marrow fat correlates with reduced bone mineral density. However, the origin of BMF cells may hold the key.

Studies have suggested that bone marrow adipose tissue cells originate from the differentiation of bone marrow mesenchymal stromal cells.¹

These skeletal stem cells are also the precursor of osteoblasts, the cells responsible for the formation of new bone tissue. This suggests the possibility that BMF accumulation might occur at the expense of osteoblast development.⁴

Osteoblasts aren't the only cells that may suffer from MAT accumulation. Studies have also found that excess BMF reduces red blood cell production in bone marrow.

Alternatively, or perhaps in combination, bone marrow fat may lower bone mineral density by secreting local factors that impair bone formation and stimulate bone resorption. Like other fat tissues, bone marrow adipose produces leptin, a hormone that exerts influence over energy homeostasis and inflammation.

Metabolism and inflammation have a direct impact on bone health and remodeling, so BMF's impact on these systemic factors could help explain its association with osteoporosis.

Synopsis

Studies offer two explanations for why accumulating bone marrow fat correlates to low bone mineral density. Bone marrow adipose cells are derived from the same bone marrow stem cells as osteoblasts, the bone-building cells. Excess BMF production may happen at the expense of osteoblast formation. Another possibility is that the hormones secreted by BMF cells are hampering the bone remodeling process.

What You Can Do About Bone Marrow Fat

Studies have observed that bone marrow fat tends to increase with aging and in the presence of a variety of metabolic, skeletal, and blood-cell related diseases.

Aging is a natural process, so rising BMF is nothing to be ashamed of– yet it's important to take steps to counteract this tendency.

A study with mice observed that bone marrow fat accumulates in response to a high-fat diet but is suppressed by daily exercise. Even more encouraging, they found that the exercise suppression of bone marrow fat occurs simultaneously with the formation of new bone.⁵

The researchers observed this effect in healthy mice fed a regular diet and in mice with diet-induced obesity. Using mRNA analysis of whole tibiae, the researchers confirmed that diet‑induced obesity was linked to greater bone marrow fat storage.

Eating a nutrient-dense diet without excessive fat and engaging in regular exercise can reduce BMF levels while building new bone mass. Bone marrow fat is associated with poor bone health, inflammation, and metabolic disorders– yet it can be kept in check with a healthy diet and active lifestyle.

Synopsis

Eating a healthy diet and getting regular exercise can help keep bone marrow fat levels low while building new bone mass.

What This Means To You

Don't let bone marrow fat threaten your bone-building potential. Eat a diet that is rich in vegetables, fruits, legumes, and whole grains. It's easy to do when you follow the 80/20 pH-balanced diet. Get regular exercise, at least 150 minutes of physical activity each week. Even better, build a workout routine focused on building healthy bones.

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No matter your fitness level or what type of workout you'd like to do, SaveTrainer has you covered. Best of all, it's available wherever you are, whenever you want to work out. That makes exercise convenient, easy, and enjoyable.

Your bone marrow is a critical tissue for maintaining your health, and now you know why it's important for building durable bones. Use this knowledge to motivate yourself to make bone-healthy choices and enjoy the active and independent life those choices make possible.