Written by Darrell Wilcox, MD
If you've cleaned up your diet, started lifting weights, cut back on alcohol, and you're still carrying stubborn fat around your midsection, the frustration is understandable. Most people in that position assume they need to do more, or try harder. What many of them need is better information.
Belly fat is not simply the result of eating too much or a lack of discipline. For many people, especially in midlife, stubborn visceral fat has a hormonal and metabolic side. That side can often be tested for and addressed. Understanding why starts with a closer look at what visceral fat is.
Not All Body Fat Behaves the Same Way
The fat you can pinch just beneath the skin is called subcutaneous fat. It's not inactive, but it's relatively harmless compared with the fat that builds up deep inside the belly, around the liver, pancreas, and intestines. That's visceral fat, and it behaves very differently.
Visceral fat is biologically active. In many ways it acts like a gland. It releases hormones and inflammatory signals that can interfere with the systems that control energy, appetite, and hormone balance. These signals are called adipokines, and their effects reach throughout the body.
When visceral fat is high, the body's response to leptin, the hormone that signals fullness, tends to be blunted, which may add to hunger even when you're eating enough. Adiponectin, a hormone that helps insulin work and calms inflammation, tends to fall. Inflammatory signals such as TNF-alpha and IL-6 tend to rise. This low-grade, body-wide inflammation is linked with heart disease, metabolic problems, and hormone changes.
Body fat, including visceral fat, also contains aromatase, an enzyme that converts testosterone and related hormones into estrogen. This matters. It means extra visceral fat may not only be a result of hormone changes. It can also add to them, especially in men, by converting more testosterone to estrogen.
Visceral fat doesn't only respond to hormone changes. It can add to them.
The Hormones Linked With Visceral Fat
Visceral fat and hormone problems often feed each other, so addressing only one may not be enough. Here's what research suggests for each major hormone.
Testosterone
In men, low testosterone and visceral fat go together, and the link seems to run both ways. Testosterone supports muscle and a healthier fat pattern. As levels fall with age, fat tends to shift toward the belly. That visceral fat can then convert more testosterone into estrogen and may dampen the signals between the brain and the testes. Over time this can become a cycle.
In women the picture is more mixed. Some studies of midlife women have linked higher free testosterone with more visceral fat. In my view, much of that link reflects women with naturally high free testosterone, a pattern typical of PCOS (now also called PMOS, polyendocrine metabolic ovarian syndrome). Women with this pattern are more likely to have obesity, and high insulin can push the ovaries to make more testosterone and lower the protein that binds it. So in these women, the metabolic problem often comes first and tends to drive the high free testosterone, rather than the other way around. Women with low testosterone also tend to gain visceral fat. In my practice, restoring testosterone to a healthy range in these women can improve metabolic rate, insulin sensitivity, and visceral fat.
Estradiol
In women, estradiol plays an underappreciated role in metabolic health. It is linked with a healthier fat pattern and better insulin sensitivity. In studies that followed women through menopause, visceral fat rose in those who reached menopause, often without big changes in diet or activity. Falling estrogen is thought to be part of the reason, along with changes in other hormones and in daily energy use. In trials of postmenopausal women, hormone therapy modestly reduced belly fat and insulin resistance. That can be one reason to consider it, alongside symptom relief, though hormone therapy is not approved as a weight loss treatment and the decision is individual.
DHEA
DHEA, together with its stored form DHEA-S, is one of the most plentiful hormones in the blood, and levels fall with age. In observational studies, low DHEA is linked with more visceral fat, lower insulin sensitivity, and more inflammation, though that doesn't show that low DHEA causes them. It gets less attention than testosterone or estradiol, but it can be a useful part of a full hormone assessment.
Thyroid, Including Free T3
Thyroid hormone helps set how much energy the body burns and how it uses fat and sugar. Free T3 is the active form. Many standard workups check only TSH. Checking free T4 and free T3 as well can add useful information when symptoms don't match a normal TSH. A free T3 at the low end of normal may be one possible contributor to visceral fat, though it isn't a proven cause. When thyroid hormone is truly low, metabolism slows and weight and insulin resistance can get worse.
Cortisol
Visceral fat cells have many cortisol receptors, which makes them sensitive to cortisol, the body's main stress hormone. Very high cortisol, as in Cushing syndrome, is well known to cause belly fat and high blood sugar. In everyday life, long-term stress is linked with more belly fat and worse insulin resistance in observational studies, though cause and effect is harder to prove. Stress and sleep are worth addressing as part of any serious plan for metabolic health.
Insulin Resistance
Insulin resistance and visceral fat are so closely tied that it's often hard to tell which came first. Visceral fat can drive insulin resistance through inflammation, adipokine changes, and fatty acids released straight to the liver. Insulin resistance, in turn, makes it easier to store more visceral fat. Working on both together tends to give more lasting results.
What We Measure, and Why It Matters
Finding visceral fat and its effects takes more than a scale or a BMI chart. BMI doesn't tell you where fat is stored or how active it is. Two people with the same BMI can have very different metabolic risk.
A full assessment can include:
Waist size and waist-to-hip ratio. Simple, but often more informative about metabolic risk than weight or BMI alone. For in-person visits at a 4Ever Young clinic, an InBody body composition scan can add an estimate of visceral fat and lean mass, giving a baseline and a way to track change over time. CT and MRI measure visceral fat most precisely, and DEXA can also estimate it, but they cost more and aren't always easy to get. For routine tracking, waist measurements plus an InBody scan give a practical picture without a radiology referral.
Fasting insulin and HOMA-IR. Practical blood tests that estimate insulin resistance. A normal fasting glucose can hide a high insulin level. In a large study of British civil servants, insulin resistance was already rising years before blood sugar crossed into diabetes.
Triglyceride to HDL ratio. A simple and often overlooked clue to insulin resistance and to smaller, denser LDL particles. A standard cholesterol panel that looks normal can still come with real heart risk in someone with visceral fat and insulin resistance.
hs-CRP. High-sensitivity C-reactive protein, a general marker of low-grade inflammation, which visceral fat can add to. It can also rise with infection, injury, and other conditions.
Adiponectin. Levels tend to be lower when visceral fat and insulin resistance are higher. Low levels are linked with higher metabolic risk, sometimes before blood sugar changes show up on a standard panel. Not every lab offers it.
SHBG (sex hormone binding globulin). Low SHBG is often linked with insulin resistance and fatty liver, and it can show up early. It can be a useful clue in women. Thyroid, liver health, age, and some medicines also affect it.
LH to FSH ratio. In women of reproductive age, FSH is generally about twice LH. In the PCOS (PMOS) pattern, which is closely tied to insulin resistance, LH is generally well above FSH. As insulin resistance builds, the ratio can start to shift in that direction, sometimes before other markers look abnormal.
Taken together, these markers give a more complete picture of metabolic health than any single number.
Our Approach: Looking for the Root Cause
One patient came to us in their mid-forties: lean by BMI standards, active, and eating well. Their complaint was belly fullness and fatigue that had slowly gotten worse over two years. Standard labs from their primary care doctor had come back normal. Our panel showed a free T3 lower than we like to see, low SHBG, a high fasting insulin consistent with early insulin resistance, and a testosterone level that was within the reference range but lower than we'd expect for their age and activity level. Within four months of a plan built around those results, their body composition had improved and their energy had returned. That's one person's experience, and results vary.
Patterns like this are not rare. The tests that can find them are widely available, but they aren't always part of routine care.
Hormone Treatment
When testing finds a real hormone problem, treating it can be one useful part of a plan. In a pooled analysis of 29 trials in middle-aged and older men, testosterone lowered body fat by about 1.6 kg and added about the same amount of lean mass. In one small trial of men with low testosterone and type 2 diabetes, it also improved insulin sensitivity and waist size. In my practice, bringing testosterone back to a healthy range in women with low levels can improve metabolic rate, insulin sensitivity, and visceral fat. Estradiol therapy around perimenopause and menopause modestly reduced belly fat and insulin resistance in trials of postmenopausal women. When testing shows a low DHEA-S level, restoring it may modestly help body composition in some people, though the trial results are mixed. For thyroid, the goal is treating a real deficiency carefully, since too much thyroid hormone carries its own risks, including to bone and heart rhythm.
Peptide Therapy
Some growth hormone-releasing medicines may help selected patients with a lot of visceral fat. Tesamorelin lowered visceral fat by about 15 percent over six months compared with placebo. Those trials were in people with HIV, a group that often really struggles with visceral fat, and it is FDA approved for that use. Whether it works as well in people without HIV is less clear. CJC-1295 and ipamorelin are other peptides in this family that some clinicians use. Neither is FDA approved.
GLP-1 Medications
For people with significant metabolic problems or insulin resistance, GLP-1 medicines are among the most effective drug options now available. In trials they do more than curb appetite. They improve blood sugar control, reduce liver fat, lower markers of inflammation, and reduce visceral fat, mostly through weight loss. The benefits tend to last as long as the medicine is continued; in one large trial, people regained much of the lost weight within a year of stopping.
GLP-1 is itself a hormone made naturally in the gut. Pooled studies have not found that people with type 2 diabetes consistently make less GLP-1 after a meal than people without it, though output may fall as blood sugar control worsens. These medicines work by giving a much stronger, longer-lasting GLP-1 signal than the body makes on its own. That's one reason we see them as part of a hormone and metabolic plan, not just a weight loss drug.
Lifestyle Integration
Clinical treatment works best alongside the basics. Exercise, both resistance and aerobic training, reduces visceral fat and improves insulin sensitivity in trials. Enough protein, good sleep, and managing stress also support metabolic health. Our role is to help patients improve the whole picture, not simply prescribe and monitor. Treatment adds to good lifestyle habits; it doesn't replace them.
If You've Been Doing the Right Things and Still Not Getting Results
The frustration of doing everything by the book and still carrying stubborn belly fat is real, and it often means something in the hormone or metabolic picture hasn't been found yet.
Visceral fat is not a character flaw. It is often a metabolic and hormonal problem, and it often responds to metabolic and hormonal treatment. The evidence supports taking a closer look. When a real hormone or metabolic problem is found and treated, body composition often improves, though the strength of the evidence differs from one treatment to the next, and long-term outcome data are still limited for several of them.
In our practice, we focus on this kind of thorough, root-cause evaluation. If you're ready to understand what may be driving your metabolic health and address it step by step, we'd be glad to have that conversation.
To request your free virtual consultation, email drwilcox@precisionhormoneconsulting.com.
Sources
- Janssen I, et al. Testosterone and visceral fat in midlife women: the SWAN fat patterning study. Obesity. 2010;18(3):604-610. PMID 19696765.
- Janssen I, et al. Covariation of change in bioavailable testosterone and adiposity in midlife women. Obesity. 2015;23(2):488-494. PMID 25557490.
- Lovejoy JC, et al. Increased visceral fat and decreased energy expenditure during the menopausal transition. Int J Obes. 2008;32(6):949-958. PMID 18332882.
- Salpeter SR, et al. Meta-analysis: effect of hormone-replacement therapy on components of the metabolic syndrome in postmenopausal women. Diabetes Obes Metab. 2006;8(5):538-554. PMID 16918589.
- Corona G, et al. Dehydroepiandrosterone supplementation in elderly men: a meta-analysis study of placebo-controlled trials. J Clin Endocrinol Metab. 2013;98(9):3615-3626. PMID 23824417.
- Villareal DT, Holloszy JO. Effect of DHEA on abdominal fat and insulin action in elderly women and men: a randomized controlled trial. JAMA. 2004;292(18):2243-2248. PMID 15536111.
- Isidori AM, et al. Effects of testosterone on body composition, bone metabolism and serum lipid profile in middle-aged men: a meta-analysis. Clin Endocrinol. 2005;63(3):280-293. PMID 16117815.
- Kapoor D, et al. Testosterone replacement therapy improves insulin resistance, glycaemic control, visceral adiposity and hypercholesterolaemia in hypogonadal men with type 2 diabetes. Eur J Endocrinol. 2006;154(6):899-906. PMID 16728551.
- Davis SR, et al. Global consensus position statement on the use of testosterone therapy for women. J Clin Endocrinol Metab. 2019;104(10):4660-4666. PMID 31498871.
- Tabák AG, et al. Trajectories of glycaemia, insulin sensitivity, and insulin secretion before diagnosis of type 2 diabetes: an analysis from the Whitehall II study. Lancet. 2009;373(9682):2215-2221. PMID 19515410.
- Falutz J, et al. Metabolic effects of a growth hormone-releasing factor in patients with HIV. N Engl J Med. 2007;357(23):2359-2370. PMID 18057338.
- Calanna S, et al. Secretion of glucagon-like peptide-1 in patients with type 2 diabetes mellitus: systematic review and meta-analyses of clinical studies. Diabetologia. 2013;56(5):965-972. PMID 23377698.
- Wilding JPH, et al. Weight regain and cardiometabolic effects after withdrawal of semaglutide: the STEP 1 trial extension. Diabetes Obes Metab. 2022;24(8):1553-1564. PMID 35441470.
Disclaimer: This content is for educational purposes only and does not constitute medical advice. Hormone therapy, peptide therapy, and GLP-1 medications are prescription treatments that require individualized evaluation, monitoring, and ongoing clinical oversight. Some therapies discussed may be used off-label. Results vary. Consult a qualified physician before beginning any new treatment.
