Osteopenia: What Your T Score Means

A DEXA report gives bone density as a T score, and many people read it the way they read a grade. Minus 1.5 sounds like a small miss. It is more useful to know what the number is actually counting, because that tells you how much room you have and how quickly it can close.

What the number counts

The T score compares your bone density with the average healthy young adult, at the age when bone is at its peak. The unit is the standard deviation, a measure of how spread out bone density is across healthy young people. A T score of minus 1 means your density sits one standard deviation below that young adult average. Each standard deviation is roughly 10 to 12% of bone density.

The cut points are simple:

• Minus 1.0 or higher is normal.
• Between minus 1.0 and minus 2.5 is osteopenia, or low bone mass.
• Minus 2.5 or lower is osteoporosis.

Fracture risk does not jump at a line. It climbs steadily as the score falls, roughly one and a half to two times higher for each standard deviation lower. That is why a minus 2.2 and a minus 1.1 are both called osteopenia but are not the same finding.

Why osteopenia matters

Osteopenia has no symptoms. Bone does not ache as it thins, and a basic lab panel does not show it. Most people learn they have low bone mass only because someone scanned them, or because they broke a wrist in a fall that should have been minor.

Because so many adults sit in the osteopenia range, a large share of all fragility fractures happen in people who were never labeled osteoporotic. The label matters less than the direction the number is moving.

That makes osteopenia a window. Bone is living tissue that is broken down and rebuilt in cycles lasting several months, and it responds to what you ask of it. At minus 1.4 there is still a lot of bone to protect.

What moves it

• Lifting. Bone responds to load. Trials of supervised heavy lifting and jumping in women with low bone mass have shown small gains at the spine, a few percent at most, and held the hip steady while women on light exercise lost bone at both.
• Protein. Bone is a protein framework with mineral laid onto it. We set protein at 1 gram per pound of lean body mass.
• Vitamin D. It controls how much calcium you absorb. We aim for a level of 60 to 80 ng/mL.
• Calcium. Roughly 1,000 to 1,200 mg a day, from food first.

Bone changes slowly, so the trend on a DEXA means the most over one to two years. A first scan sets the baseline the rest are measured against.

That's why we check it.

Book a DEXA scan at HYBRD Health ($199)

This article is educational and is not medical advice.