When you think about getting healthier, is weight loss the first (or only) thing that comes to mind? When you visit the doctor, is one of the first things s/he mentions your weight? Have you been chasing a number on the scale in the pursuit of health?
As you’re about to find out, health isn’t defined by a number on the scale. In fact, weight may have a lot less to do with health than you think. Instead, here are five measurements that really matter (when it comes to mortality, or death, the hardest of measurable endpoints). Chances are if you improve in these five areas, you’ll enjoy quality weight loss as an added bonus.
#1 Physical Activity
Dr. James Levine, a world authority on obesity research and professor of medicine at the Mayo Clinic, has been quoted, “Sitting is more dangerous than smoking, kills more people than HIV, and is more treacherous than parachuting. We are sitting ourselves to death.” In a study published in the journal The Lancet, a highly respected group of researchers estimated that physical activity causes as many deaths each year as smoking.1
There’s no question there’s compelling and accumulating evidence that being sedentary is associated with increased mortality.2,3 This is quite alarming considering adults are sedentary for a whopping 9 – 10 hour per day (not including sleeping).4
Despite the accuracy of advising, “Sit less, move more,” it’s not all that helpful.5 And the crazy thing is that regular exercise (at least up to the currently recommended levels) alone is probably not enough to offset the potential harmful effects of sitting so many hours a day. After all, research shows that “both the total volume of sedentary time and its accrual in prolonged, uninterrupted bouts are associated with all-cause mortality.”3
Ready for some encouraging news? Research shows that a sedentary person who increases his step count from < 1,000 to meet the popular 10,000-step guideline cuts his/her risk of death nearly in half (46%)!6
Take-Home: Move more and sit less…just kidding! Using a fitness/step tracker (e.g., Fitbit®, Samsung Gear, or Garmin), aim for 7,000 – 10,000 steps per day. In addition to overall volume, break up periods of sitting still by setting an alarm to get up and move at least once every hour.
This may surprise some folks, but muscular strength is one of the strongest predictors of how long you live. In fact, a number of studies have shown that muscular strength is inversely associated with death from all causes. Even more interesting, strength protects against death independent of cardiorespiratory fitness. (We’ll touch on that in a moment.)7
In these studies, muscular strength has been assessed through handgrip tests, bench press (upper body strength), and seated leg press (lower body strength). But let’s not get carried away with the tests themselves. Instead, let’s consider how someone increases and maintains strength throughout a lifetime: RESISTANCE TRAINING. We’ve talked about its importance on the blog and our podcast, including why it’s the single-most important type of exercise you can do for healthy aging.
Simply put, regularly lifting weights enhances muscular strength and endurance, muscle mass, functional capacity, daily physical activity, risk profile for cardiovascular disease, and quality of life, all factors that are well-known predictors of higher risk of morality.8 Think of the improvement in functional capacity alone, for example, or reducing the risk of falling, which typically leads to a downhill spiral of health issues.
Moral of the story: For awesome health, lift weights, lift them regularly, and when you do, push yourself—degree of effort really counts!
Take-Home: Generally speaking, it’s also a good idea to exercise each of your major body parts 2 – 3 times a week, and “compound movements,” like squats, presses, and rows, that use multiple muscle groups give you the best bang for the buck.
If muscular strength is important for health, then it probably isn’t a shocker that cardiorespiratory fitness (CRF) is too. In fact, CRF, which is typically defined by a measure of aerobic capacity called VO2max, is arguably one of the strongest predictors of health.
Indeed, handfuls of studies have shown that CRF is inversely associated with a lower risk of death from all causes.9 Get this, better fitness (even moderate levels of CRF) can lower the risk of mortality by 60 – 70%!10 Even though death is inevitable, this is clear evidence that physical fitness can have an enormous impact on living long and living well.
If you’re wondering how much, there’s even better news. Studies show significant risk reductions for premature death even when the volume of exercise is well below the typically recommended targets—starting at HALF the normal prescription. In other words, something is better than nothing.
Take-Home: Higher levels of fitness equal better health. It’s as simple as that. (Up to a point. Yes, there is such thing as “too much of a good thing.”) The traditional recommendation is at least 150 minutes/week of moderate-intensity “cardio.” But, you may be able to get more bang for your fitness buck by exercising at a higher intensity (e.g., HIIT) for a shorter period of time (≤ 75minutes/week).
#4 Waist Circumference
Okay, so fitness is important, but what about fatness? Believe it or not, our fixation with weight loss may not be justified. Despite the fact that it’s constantly beaten into our heads that being overweight—and even obese—is unhealthy, the truth is that research shows that being overweight is associated with lower all-cause mortality. And grade 1 obesity is NOT associated with higher mortality.11 However, the higher ends of the obesity spectrum (i.e., BMI < 35) are indeed associated with increased mortality. This phenomenon, which highlights better health outcomes (including lower mortality rates) in overweight and obese folks (compared with normal-weight people), is often referred to as the “obesity paradox.”12 You may have even heard the expression “fat and fit.” This refers to folks who are classified (by BMI standards) as overweight or obese but “metabolically healthy” (MHO).
On the flip side, it’s completely possible to be “normal” weight yet have a high body fat percentage (and in particular, excess abdominal fat). This is known as “normal-weight obesity” (also, “skinny fat”) and is associated with a higher risk of mortality.13,14
While there is controversy over the validity of MHO, this highlights that weight alone is not such a great indicator of health. Rather, how much body fat and (more importantly) how our body fat is distributed seem to be more telling factors. Along these lines, there’s no question that excess belly fat, also referred to as central or abdominal obesity, is strongly associated with mortality.
Take-Home: Instead of being so weight-conscious and scale-centric, waist circumference, waist-to-hip ratio, and even waist-to-height ratios seem to be much better indicators of abdominal obesity and, therefore, health. Here are some guidelines for each:
- Men: < 94 cm or <37 in
- Women: < 80 cm or <31.5 in
- Men: < 0.90
- Women: < 0.85
Waist-to-height ratio: < 0.59 (for both men and women)
NOTE: Counting calories can also be a useful tool, but not necessarily for the reason most think. Most people count calories for weight loss, but long-term caloric restriction is one of the most effective, research-backed tools for extending lifespan.15,16 I don’t know about you, but restricting calories by up to 40% EVERY day doesn’t sound like much fun. Thank goodness for strategies like the fast-mimicking diets and time-restricted feeding, which may offer similar longevity benefits!
#5 Blood Sugar Management
In case you haven’t noticed, there’s been no mention of some of the more popular health metrics, such as total and LDL cholesterol. That’s not to say those variables aren’t important. However, our understanding of them is evolving, and it may not be as simple as we’ve been led to believe over the years (i.e., cholesterol hypothesis).17,18
However, one measurement (which unfortunately is often omitted from routine labs) that may be particularly worth keeping tabs on is glycated (or glycosylated) hemoglobin. It also goes by the acronym HbA1c. Basically, HbA1c is a robust biomarker of the preceding 2 – 3 months’ average blood glucose level. In other words, it’s a relatively long-term measure of one’s blood glucose control (i.e., glycemic control).19
Research has shown that HbA1c is a key predictor of mortality. What’s even more interesting is that HbA1c predicts mortality independently of fasting blood glucose, a more commonly tested biomarker.20,21 In other words, “healthy” fasting blood glucose levels can be misleading.
Keep in mind that “the glycemic response is a personal attribute.” As we’ve previously discussed, relying solely on the glycemic index may be misleading.22 Along those lines, recent research (The Personalized Nutrition Project) suggests that “personalized diets,” based on individual glycemic responses, may be the next frontier of nutrition.23
Take-Home: Glycemic control (i.e., blood glucose management) seems to be one of the most important health biomarkers to monitor. Exercise (and in particular, high-intensity exercise such as HIIT and weight training) and carbohydrate-controlled diets (e.g., low- to moderate-carbohydrate, ketogenic diet) are the lifestyle factors that most effectively improve glycemic control.
NOTE: If you like to “geek out” on lab work, another biomarker of aging that may be worth tracking is C-reactive protein (CRP). This is a marker of inflammation. While research shows that CRP “robustly associates” with an increased risk of death from all causes, keep in mind that it does not seem to be causal.24 In other words, modifiable lifestyle factors, which influence CRP levels, including those we’ve already mentioned (e.g., blood sugar management, physical activity levels, abdominal obesity), appear to be more important targets than CRP itself.25
If you’ve been chasing a number on the scale or are convinced that weight loss is the ultimate health goal, maybe it’s time to think again. Instead, shift your focus to the areas and metrics shared above. Better yet, concentrate on the behaviors that lead to improvements in these areas, and you’ll live longer, better, and leaner.