I’ve run a LOT of DEXA body fat scans during my health career, but even with a trained eye, I can guarantee you can’t always tell who’s fit or fat just by eyeing up the person.
Some people appear to have a lot of fat when, in fact, their fat percentage is low and they carry a lot of muscle.
Others look skinny but actually carry a lot of fat and little muscle.
The DEXA comparison image shows a man with a lot of muscle and very little subcutaneous fat and a woman who carries comparatively more fat and less muscle.
I get looks of despair when people find out their percentage is higher than they thought and tears of joy when lower than expected.
However, body composition results need to be properly interpreted and put into context for each individual.
Please read my article on fat mass index which sheds light on this common misunderstanding.
What is a “normal” body fat percentage anyway?
I don’t like drawing a dichotomous line in the sand when it comes to so-called “norms” charts.
I think it’s important that people understand they’re only a general guideline and that what’s too much or too little for one person may be different for the next.
Whether a woman is 30.9% (“acceptable”) or 31.1% (“overweight”), the difference is purely academic and she probably won’t look much different (or suffer a massive heart attack) with the extra 0.2 percent pushing her into the next classification.
How much is too much fat?
Clients often ask me if they have too much body fat. My answer to this question is always the same: too much fat for what?
The question must be further qualified by asking WHY their body fat percent is important to them.
- Are they focused on their body composition and its relationship to health problems?
- Or are they only concerned about aesthetics and wanting to look like a ripped fitness model?
How does fat relate to health?
Excessive fat is associated with many health problems including type 2 diabetes and heart disease.
However, our understanding of body fat has evolved over the years and we now understand that it’s not always the total amount of body fat but where it’s located on your body.
Visceral fat refers to the deep belly fat inside your abdomen which wraps around your organs and secretes substances into the bloodstream known as cytokines.
There are many different types of cytokines and they exert a variety of effects such as blood vessel constriction (high blood pressure) or inflammation which can contribute to the development of both diabetes and heart disease.
How much visceral fat can I have before it causes health problems?
Research has demonstrated that when we look across the population and stuff everyone under the bell curve, a visceral fat area ranging from 10 to 100 cm² is considered normal and at around 100 cm² the risk for heart and metabolic problems begins to increase.
I think it’s important to note that the visceral fat threshold for the onset of disease will vary from person to person.
For example, a man with a strong family history of early-onset heart attacks on the male side of his family might have a lower individual visceral fat threshold of, say, 80 cm².
On the other hand, a woman with the longevity gene and a pack a day cigarette habit could plausibly have a threshold of 130 cm².
Fat distribution: apple versus pear body shape and health risk
We tend to associate an apple-shaped body (more central fat) with health risk and a pear-shaped body (more hip and thigh fat) with a comparatively lower risk.
However, a study out of UC Davis suggests that lower body fat is associated with an increase in cytokines linked to the development of heart disease and diabetes.
This is just a single small study and would still need to be corroborated by more trials which can establish a cause and effect relationship between lower body fat and health risk.
Low body fat, aesthetics, and public perception
I’ve seen DEXA reports on women with 20% body fat and a visceral fat area of 20 cm².
These were fit women who exercised daily, didn’t smoke, drank little alcohol, and were careful with their diets.
Yet no matter how much I reassured them, they were convinced their body fat percentage was too high and they were determined to get down to 15%.
This raises questions about the battle between body fat, aesthetics, health, and the role the media and advertising play in distorted body images.
The nonstop barrage of subliminal “thin is in” and “nobody will love you unless you’re perfect” health messages have created a disconnect between what ACTUALLY constitutes a healthy fat percentage and what people THINK is a healthy fat percentage.
How low is too low for body fat percentage?
So how low can your body fat go before it causes problems?
As with visceral fat, the low-end threshold at which your body fat is “too low” is different for everyone.
I would say that, for women, when body fat percentages approach the low teens, or for men down in the single digits, then it’s time to pay attention to any changes in your body’s physiology, such as a loss of menstrual cycle, or feeling tired, getting sick more frequently.
Don’t forget, fat is your friend
Despite all the bad press it receives, fat is important for our survival and normal biological functions.
Don’t get too hung up on norm charts and don’t compare yourself to the models on the covers of fitness magazines.
Assume a more health-focused perspective and work on keeping your visceral fat levels to a minimum.
And remember, body fat is only a single biomarker and other lifestyle factors such as exercise, diet, smoking, and stress must be taken into consideration.
Hi Bill
i respect your work and wondered if you could answer this for me. I had a client come to me yesterday 25% body fat 9 stone 8 and 5 feet 1 inches. She worked out 3 times a week combining wieghts with HIITS and running. She wanted to drop body fat but not weight. I could only think of increasing intensity or volume of training while possibly decreasing carbs and increasing protein but as she did not want to cut calories I was baffled. Is this an area where there is so much conflicting advise its just confusing or is it simply the energy expenditure equation again. Thanks Lisa
Hi Lisa, Thanks for your comment. I know there are all kinds of combinations of approaches and some will work better than others. But I am a big fan of “first do no long term damage to the person’s physiology.” The body doesn’t give a sh*t about us wanting to be fit or look good for a wedding or class reunion. The body only knows homeostasis (don’t rock the boat!). So for as much as we push the body to change, particularly with radical changes to diet and exercise, the more it will tend to fight back to maintain exactly where it is. An old cardiac rehab patient of mine was a stock broker and I once asked him jokingly for a stock tip. He responded with something very profound that I carry with me to this day, “It’s not about timing the market. It’s about time IN the market.” In other words, set a strategy in place that encourages small changes and stick with it. Radical programs that are a shock to the system will likely fail in the long-term.
In your client’s case, she is 25% fat (which is not astronomical), 60.9 kg or 134 lbs (if my math is correct), and 155 cm in height [I do conversions for other readers]. There are three ways to create a calorie deficit: One is by reducing calorie intake (eat less), second is by increasing energy expenditure (exercise), and third is a combination of both. Based on what you’ve provided, she is opting for the first option (cane herself). However, if she’s pummelling herself to a bloody pulp then it would call into question how sustainable her plan of attack is going to be. Whilst it is true that genes and hormones will play a role in dictating how easy or difficult it is for her to lose fat, if she’s prepared to make those small changes for the long-term and (wait for it) be patient, then she will probably shave off a bit of body fat without having to significantly reduce calories. In her case it might also be a good idea for her to get a resting metabolic rate test done so she can have a more scientific idea of how many calories she really needs.
If she doesn’t want to cut calories, then the question is also how much is she currently eating? And how accurate is the number she comes up with? If she was eating 1900 calories, then she could probably get away with shaving off a couple hundred calories without initiating the famine response. If she goes too low, as in 1200 calories or less, then her body’s physiology is likely to get a bit jittery and start to respond by holding onto her fat stores.
There are people out there that say “calories in vs. calories out is bullish*t.” Whilst we do know more now about the influences of other factors like genetics and hormones/neurotransmitters, the base of it is still a case of energy in vs energy out. But that threshold can vary from person to person depending on things like metabolic efficiency vs metabolic inefficiency (related to uncoupling proteins UCPs). You can Google it. Quite fascinating stuff.
Bottom line in your client’s case: yes it is still related to calories in vs. calories out and she will need to make changes. Flogging herself is unlikely to be sustainable in the long-term depending on how much of a shock to her system it is. She could probably get away with a little extra protein since that can enhance the TEF (https://en.wikipedia.org/wiki/Specific_dynamic_action). Finally, look at the check-up from the neck up approach. Is she being realistic with herself? How much does she want to lose and in what time frame? She might require a bit of education and putting her expectations into perspective.
Hope this helps
Bill
Hiii Bill…I’m a fitness trainer n a dietician…. I’d like to understand the concept of visceral fat a lil better.. In d sense if anyone s vis.fat is very low n is going down lower with a n exercise regime….how advisable is it to have very low visceral fat…. I.e..from 2—10..is d normal range but if someone has less den 2….how do we get to increase dis levels..pl advice
Hi Bella,
I think normative ranges for anything can be a general guide, but you always have to consider the individual and what’s healthy for that person. As I said in my article, what’s normal and healthy for one person could plausibly be too much (or too little) for someone else. In the example you’ve referred to, I’d be looking into if the person’s health is compromised due to their fat being too low. If not, then why fix something that isn’t broken?
Hi, in answer to Lisa;
I’m 49 work a mad schedule in the corporate world of 12-18 hours a day, need very little sleep but made a point a taking 3 hours a day for me. I work out 5-6 times a week mostly weight (hate cardio although I would do a weekly spinning class) and over the last year decided to reshape my body from OK to really good!
I’m 1.75m and my weight fluctuates between 55 and 58.5kg with a body fat mass around 22%. On paper not bad in reality felt flabby and out of shape.
I worked in 2 things diet and training. I started with dietician to make sure I would not do anything crazy and get in the right path and then made it fit for me.
I increased the amount of lean protein (egg white omelette, fish, little meat, low fat protein-whey impact isolate unflavoured), kept loads of green veg, added fat to my diet (avocado, nuts), always been super low carbs, few berries and chocolate every day (can’t live both out my super dark few squares), virtually no alcohol champagne on Friday! Skinny cappuccino and tea are on every day!
I changed my training to heavier weights with less reps (don’t want bulk) and working out with an ex body builder who controls my posture and counts the rep (he does not take no or I can’t as an answer).
In short after one year I have not lost weight, I’m now 57kg but my body fat has dropped to 7.5% my body is pure lean muscle does not look skinny or over muscular and the last full medical checkup gave me a physiological age of 22-24. I still need to do more work out to tighten my core further but the transformation is amazing no flab in sight and the bad circulation with swollen ankles has almost disappeared.
It’s a lot of discipline but so worth it; I did not aim at a such a low body fat it just happened and thank god I’m not looking skinny probably c’ause I did not lose weight and I’m passionate about food and cooking which is the core of a healthy diet.
Anna
All forms of bodyfat percentage measurement currently being embraced by fitness professionals and enthusiasts are actually highly variable and potentially wildly inaccurate at the individual level. DEXA is not purely empirical, contrary to common belief. It too relies on a predictive algorithm that assumes your most likely fat mass for your age and gender (ie. according to general norms).
Hi Alison,
You’d be correct. The different methodologies can give massively disparate results. I’ve taught exercise physiologists and personal trainers all the different testing modalities and have had each student measure all their classmates and then I plotted them in a spreadsheet and graph to show how much of a difference there is between assessors. It’s huge. At least with DEXA, provided proper protocol is followed, we tend to see more intrasubject accuracy and reliability. But if you really want 100% accuracy, then cadaver dissection is the way to go. But unfortunately you don’t get many volunteers for that!
If I workout and play outside I end up with a great, lively body, with 20%body fat. And the way I prefer it to look eg athletic. But medium term anything below 22% halts my she-flows (aka menstrual cycle ) and long term I discovered that it’s an.energy deficit that stresses other hormonal systems including adrenal andthyroid. RED-S is an easy trap to fall into. If you are not a competitive athlete, and just like moving your body for fun, then you may not realise you need to eat like an athlete. Many female athletes welcome a loss of menstrual cycle but don’t realise the long term effects.
I saw a news report saying that sumo wrestlers can be healthy because they overeat but also exercise, and that causes adipose but visceral fat. Not sure of the validity!
Hi Claire, Yep, you make a good point. Everyone is a bit different, but after running countless dexa scans on athletic women, I can tell you one thing’s for sure. There are a lot of really ripped women out there with anomalously low body fat who can barely remember when their last menstrual cycle was. So whilst they might be the Instagram muses for many aspiring female bodybuilders and figure competitors, there is an unspoken downside to it all that is often ignored (oftentimes wilfully). The threshold at which a woman loses her menstrual cycle varies from person to person, but it’s important for each woman to know where that line is. As for the sumo wrestler, not sure. I haven’t seen that study! Thanks for taking the time to leave a comment 🙂
I am Female 32y old
height 1.65 m
weight 58 kg
fat weight 22.376 kg
lean weight 33.619 kg
android 34.8%
gynoid 47.2%
A/G ratio .74
BMC 2.657
tissue fat % is 40%
I need your advice plz ,as you are the only doctor with logic thoughts .
I am in good health ? should I gain more muscles and lose fat ?
any advice plz.
Hi Nesreen,
I cannot tell you if you’re healthy just by body composition numbers. Body composition (how much muscle and fat you have) is only one single biomarker of health. If you’re concerned, the best course of action is for you to make an appointment with your doctor and have a physical health screen conducted. The reason for this is that it is possible to carry body fat and be healthy on the inside (i.e., normal blood pressure, normal blood sugar). So it’s not always a simple case of “too much fat = unhealthy.” It really depends on the individual and their overall lifestyle habits. Bottom line: I would suggest that you not get too fixated ONLY on body fat and muscle, but look at the big picture. Once you have a health physical completed, at least then you will have some concrete starting numbers to work with and then you can make a plan (i.e., making healthy changes to your exercise, eating habits, reducing stress, etc).
Hope this helps.
Kind regards,
Bill
already I made full checkup
my blood sugar and pressuer is ideal
my lipid profile ideal
kidney function liver function ideal
vitamin D 83
no any deficiency in any minerals or vitamin
I am following Keto Diet from 6 months.
I had H pylori but now I am Ok .
only my concern is is 40% body fat is too mcuh .. and is there is any advise plz?
plus I started doing exercises and taking Amino acids since my protein and creatinine is low .
thank you so much for your reply <3
Hi Nesreen,
Thanks for your comment and the additional details. As a “general” rule, the higher your body fat, the greater your potential health risk. While you’re still young and your blood biomarkers are still within normal limits, then you have time to make changes. The problem for some people is that once their body fat causes health problems, it can be difficult to reverse them. So right here and now, you’re on the better side of the equation.
Regarding the keto diet, while you might initially lose weight early on, I do not believe this diet is sustainable over the long-term (1 year, 3 years, 5 years and beyond) because you cannot remain indefinitely in ketosis for the rest of your life. I would recommend looking into a more Mediterranean style of eating which is high in nutrient-dense fruits and vegetables, monounsaturated fats, lean meats etc, and will deliver a much more nutrient rich diet than the so-called “keto diet” (which is just a new trendy brand name for the same old tired high fat/protein diet that has been around forever). I would recommend visiting a university-qualified dietitian that can help you develop healthy eating strategies that are grounded in science and are sustainable over the long-term.
Exercise is also an important cornerstone for helping to improve your overall metabolic health. You will hear idiots on social media and on quack websites say stupid things like “exercise doesn’t help with weight loss.” But this is a naive view that ignores mountains of epidemiological evidence that shows exercise has a vast number of health benefits beyond just body weight as a single health biomarker.
In general, my recommendation is to focus on being as healthy as you can on the inside first and then you will find that your body weight will come into line naturally on its own. Society’s fixation ONLY on body weight and appearance is a problem and ignores the value of being healthy on the inside (i.e., your blood sugar, blood pressure, etc). Please be sure to work with your medical management team over time to monitor your blood chemistry and ensure that everything is moving in the right direction.
Hope this helps.
Kind regards,
Bill
Appreciate your kind support 🙂
thank you so much