The Spare Tire and Your Risk of Lethal Prostate Cancer

Note: I’m not fat shaming!  I am excited, because here is something you can do to lower your risk of dying of prostate cancer!

Fat is flammable.  There’s so much fat in bacon grease, you can use it as a fire starter.   You can also take a can of Crisco, stick a wick in it, and make an emergency candle.      

Unfortunately, the same is true for us:  excess body fat is like lighter fluid for prostate cancer.   Visceral fat, that “spare tire” around the abdomen, is even worse.  It’s not subcutaneous fat – the surface fat you can “pinch an inch” with.  It’s deep inside the belly, an evil pillow that settles over and wraps itself around our abdominal organs.

Visceral fat is the Jabba the Hutt of fat: a notorious villain in several important health problems.  Visceral fat raises your risk of heart disease, diabetes, metabolic disturbances, dementia, and in women, breast cancer.

Now, for the first time, it’s also been shown to raise your risk of getting prostate cancer – the aggressive kind that needs to be treated.  The kind of prostate cancer that kills.

Why is visceral fat so bad?  Because it’s like a blobby smokestack, polluting our bodies with its troublesome emissions.  “Visceral fat is a living, biologically active entity,” says medical oncologist and molecular biologist Jonathan Simons, M.D., CEO of the Prostate Cancer Foundation (PCF).  Like the chest-bursting alien in Ridley Scott’s iconic movie, it’s alive! And it’s up to no good.

Among other things, visceral fat messes with your hormones.  It lowers testosterone and raises estradiol, a form of estrogen.  It churns out inflammatory chemicals called cytokines, which can raise your blood pressure, affect blood clotting, and raise your risk of heart disease and stroke.  Cytokines also have a bad influence on your insulin resistance; this rising tide of glucose raises your risk of getting diabetes.

Like Charlie Brown’s friend, Pigpen, visceral fat also sheds – not dust, but fatty acids, which go right to the liver.  These fatty acids lower your good cholesterol and raise your bad cholesterol.

No one had connected visceral fat to prostate cancer until very recently.  In a study published in Cancer, which I recently covered for the PCF’s website, scientists led by Lorelei Mucci, Sc.D, of Harvard’s T.H. Chan School of Public Health, and Sarah Markt, Sc.D., now at Case Western, investigated body fat distribution and the risk of prostate cancer.  You might say that their study, of Icelandic men in the Age, Gene/Environment Susceptibility-Reykjavik Study, has shaken up the apple cart of what we understand about body fat.

Speaking of apples, visceral fat goes with the “apple” body shape.  This is bad, because the fat surrounds so many vital organs.  But what if you’re a “pear?”  If you’re a pear shape, you carry your fat lower, in the hips and thighs. This fat is usually subcutaneous fat, usually not thought to be as dangerous as visceral fat.

Guess what?  For prostate cancer, thigh fat is bad, too.  This study found that men with greater visceral abdominal fat as well as men with greater thigh subcutaneous fat are more likely to get advanced or fatal prostate cancer.  Visceral fat even raises the risk of advanced or fatal prostate cancer in men with a lower body mass index (BMI – for how to calculate yours, see below); this suggests that the location (even for a modest pot belly) is more important than the overall amount of body fat.

            Risk Goes Up with Higher BMI:  Each BMI increase of 5 was associated with a 52 percent higher risk of advanced prostate cancer, and a 56-percent higher risk of fatal prostate cancer.  Obese men – with a BMI of 30 or higher – were 2.5 times more likely to develop advanced disease, and 2.6 times more likely to die of prostate cancer.  For about every four-inch increase in waist circumference, the risks of getting advanced prostate cancer and dying of it went up significantly – by 40 percent and 45 percent, respectively.

This study may lead to important changes in medical practice.  “We are working very hard to save the lives of men who have advanced, aggressive prostate cancer, notes Simons.  “To do this, we are trying to understand in depth the genetics and consequences in the biochemistry of the disease, and are looking for ‘’druggable” targets for new classes of drugs.  Here is a risk factor for aggressive disease that can be changed!  If this applies to you, we want you to know what a difference you can make in your risk of dying of prostate cancer.”

Note:  Stress makes it harder for you to lose weight.  If you are stressed, your body makes more cortisol, and cortisol makes your body store more visceral fat.  On some ancient level, your body may be thinking:  “Oh, no, times are hard! We’re going to starve!  Better hang on to this fat!”  So, in addition to other ways to lose the fat – exercise and eating a smarter diet with fewer carbs and sugar – you might consider stress management strategies like meditation, relaxation techniques, and deep breathing.  It might help your body let go of the fat.

What’s My BMI? 

BMI, or body mass index, is a measure of body size – and whether you’re at a good weight for your height.  It’s pretty simple, and requires just these two things: your weight and your height.  That’s it.  You can do it yourself with this formula:  BMI = weight in pounds x 703/in^2. 

Or, you can use a BMI calculator.  There are plenty of them online.  The National Heart, Lung, and Blood Institute has a BMI calculator and even a free BMI calculator app you can download.  A BMI of 18.5-24.9 is considered the healthy range; between 25.0 and 29.9 is considered overweight, and a BMI over 30 is considered obese.  Also, men with a waistline that measures 40 inches or more are more likely to have too much visceral fat.

In addition to the book, I have written about this story and much more about prostate cancer on the Prostate Cancer Foundation’s website, pcf.org. The stories I’ve written are under the categories, “Understanding Prostate Cancer,” and “For Patients.”  As Patrick Walsh and I have said for years in our books, Knowledge is power: Saving your life may start with you going to the doctor, and knowing the right questions to ask. I hope all men will put prostate cancer on their radar. Get a baseline PSA blood test in your early 40s, and if you are of African descent, or if cancer and/or prostate cancer runs in your family, you need to be screened regularly for the disease. Many doctors don’t do this, so it’s up to you to ask for it.

© Janet Farrar Worthington