Guest post by Sean Flanagan
Nowadays more and more people are becoming aware of how weight is an imperfect predictor of health outcomes and the shortcomings of the body mass index for those with significant muscle mass. The current state of evidence suggests that activity is more important than weight, but does that mean that body fat isn’t worth thinking about at all?
In this post, I’m going to talk about how to view weight in its proper context of health. We’ll discuss the role of body fat in health, how to minimize your cardiovascular risk factors, as well as how much you should even focus on weight in the first place for having success changing your body composition.
The Two Biggest Limitations for Weight as a Predictor of Health
- Weight doesn’t necessarily reflect level of leanness. We’ve all heard about the silliness of labeling heavily muscled lean athletes as “overweight” because of their body mass index. But a more common issue that can slip through the cracks of the body mass index is that you can be a “normal weight” but still high body fat levels due to having low amounts of muscle mass.
- Activity levels matter more. Your cardiovascular risk factors are lower if you’re overweight but active than if you’re normal weight but inactive.
But does this mean it’s time to say “F It” and never think about body mass again?
Just because weight is an imperfect predictor for health does NOT mean that body mass isn’t worth thinking about. While it is better to be active and overweight than inactive and normal weight, you would still benefit from being both active AND have body fat within reasonable limits. The issue is not that it’s useless to think about body mass; the issue is that looking at weight, especially by itself, doesn’t tell the full story.
Why Fat Mass DOES Matter
Moving past an overly generalized view of weight, let’s talk about body fat. It’s common to think about body fat simply as this thing that stores calories and sits between our skin and our muscles. The reality is though that body fat doesn’t just sit there; it’s actually playing an active role in your body.
Adipose tissue is more accurately thought of as your body’s largest endocrine gland. Not only are hormones such as leptin released from adipose tissue, but chemicals such as inflammatory cytokines are also released from body fat.
It is these inflammatory cytokines that are the main reason we should respect the impact of body fat on health. As body fat levels increase, so does the release of cytokines such as tumor necrosis factor alpha and interleukin-6. Elevated levels of these and other chemicals increased by increased body fat are play roles in cardiovascular disease, diabetes, migraines, fatigue, and more.
Visceral fat is considered by many experts to be more dangerous than subcutaneous fat. Visceral fat is the fat underneath your abdominals and around your organs; it’s not the stuff you can pinch (that would be subcutaneous fat) but it does increase the size of your waist.
So where does this bring us? Excessive body fat can indeed impact your health and we can use waist circumference as a more precise benchmark than weight due to the impacts of visceral fat.
The state of having a waist size considered excessive is referred to as abdominal obesity or central obesity. Waist size is its own valid assessment tool, but also waist-to-hip ratio is as well.
Below are some of the different bench marks used by different health organizations for defining abdominal obesity:
American Heart Association and National Heart, Lung and Blood Institute (Waist Circumference): Women: > 88 cm (35 inches), Men: > 102 cm (40 inches)*
World Health Organization (Waist-to-hip ratio) : Women: > 0.85, Men: > 0.9
*It’s worth emphasizing that these thresholds are for determining who is at the highest risk. Getting further away from the cut-off (to a point) yields greater risk reduction. The UK’s National Health Service recommends that men have a waist measurement no greater than 37 inches for men and no greater than 31.5 inches for women.
How Much Should You Freak Out and What Should You Do About It?
Okay… so maybe you just grabbed a piece of measuring tape discovered that your waist measurement is about the cut off. What should you do?
Well unless medically advised otherwise, you should focus on developing health supporting habits as well as habits that will allow you to enter a calorie deficit.
In other words, not much changes if you were working on improving your health and/or losing body fat before.
If you’ve been exclusively focused on weight and calories in vs out before, I would suggest not just being mindful of waist circumference, but also taking an honest inventory on how much your habits are supporting your health goals. This is important on two levels:
- 1) As we talked about early on, being active is SUPER important for health. We also discussed how body fat (both visceral and subcutaneous) can act like an endocrine gland, releasing inflammatory cytokines. So it’s essentially not visceral fat (the more harmful to your health of the two) VS physical activity; BOTH matter. So if the degree of a calorie deficit you’re aiming for does not allow you to be active, it would be wise to start eating the food in a way that enables you to support a healthy weight AND activity level.
and 2) There appears to be at least some relationship between healthy habits and protection from visceral fat. A 5-year study from the Wake Forest Baptist Medical Center found that for every 10 grams of soluble fiber eaten daily, visceral fat decreased by 3.7% over the next 5 years. Some experts also suggest that exercise, and often aerobic exercise especially, are effective for reducing visceral fat levels.
And if you were working on health supportive behavior changes but were convinced that body mass isn’t a risk factor so you’ve avoided habits that support creating a calorie deficit, it would be wise to also look at what changes you can make that would support eating fewer – and/or burning more – calories per day. You don’t need to throw away the healthy habits you’ve made and go on a crazy diet, you just need to apply the same mentality that enabled you to create behaviors that support your health towards habits that make it easier to create a calorie deficit.
You can read more about my 4 types of habits for fat loss I wrote about in a previous guest post HERE.
Although weight isn’t the only thing that matters for your health, and your healthy habits are ALWAYS great, it would be a major act of self-deception to internalize that body mass has no importance whatsoever.
Waist circumference (and waist-to-hip ratios) is an evidence-based means of assessing disease risk. And although you should put most of your brainpower towards having consistency with the health habits you’re working on, it would be well advised to save a little bit of awareness for what is happening to your midsection and to be skeptical of the judgment of any health “experts” who claim that body mass has no importance.
Body positivity and self-compassion are both great tools that support a happy and healthy life, but denial of the evidence on abdominal obesity is not required in order to be body-positive or self-compassionate.
Sean Flanagan is a fitness & nutrition coach helping people implement habit-based strategies for lasting fat loss. Sean and Amber co-run the Habit Project, for which the next 12 Week On-Ramp is enrolling soon. You can get on the presale list and be one of the first notified of enrollment at http://seanflanaganwellness.com/on-ramp-coming-soon