One-Third of Slim American Adults Have Pre-Diabetes

It's often assumed that in order to develop type 2 diabetes, you have to be overweight. While it's true that excess weight is clearly associated with insulin resistance and diabetes, it's the insulin resistance — not necessarily the weight gain — that drives the disease.

As such, many people with a healthy weight are not metabolically healthy, putting them at risk of diseases like type 2 diabetes — even without being overweight or obese.

One of the greatest risk factors, according to University of Florida researchers, is actually inactivity, which drives up your risk of pre-diabetes regardless of your weight.

Inactivity Is Associated With Pre-Diabetes, Even if You're a Healthy Weight

If you were looking for motivation to get moving, this study, published in the American Journal of Preventive Medicine, is as good as it gets.1

In a survey of more than 1,100 healthy-weight individuals, those who were inactive (physically active for less than 30 minutes per week) were more likely to have an A1C level of 5.7 or higher, which is considered to be pre-diabetic.

Among all the inactive participants (aged 20 and over), about one-quarter were either pre-diabetic or diabetic. When only those inactive people aged 40 and over were analyzed, the percentage rose to 40 percent.

The researchers suggested that people who live a largely sedentary lifestyle yet have a healthy weight may have "normal-weight obesity or 'skinny fat,'" which they described as a "high proportion of fat to lean muscle."2

"Don't focus solely on the scale and think you're OK. If you have a sedentary lifestyle, make sure you get up and move," lead author Arch Mainous III, chair of health services research, management and policy in the University of Florida's College of Public Health and Health Professions, said in a news release.3

The researchers also noted that their findings suggest "healthy weight individuals may benefit from physical exercise,"4 which isn't exactly groundbreaking advice — but it's incredibly important nonetheless.

Weight Doesn't Always Reveal a Person's Metabolic Health

Weight isn't always an accurate tool by which to gauge metabolic health, and research by Dr. Robert Lustig, professor of pediatric endocrinology at the University of California, San Francisco (USCF), bears this out.

Lustig is perhaps best known for speaking out about the health risks of sugar, but in our 2015 interview he explained the problem with "judging a book by its cover" in terms of weight and health.

More than two-thirds of the American population is overweight or obese. About 50 percent have diabetes or pre-diabetes,5 and 1 out of every 3 have high blood pressure.6 Many also have high serum triglycerides, which is a risk factor for heart disease and stroke. Insulin resistance is a component of all of these health issues.

According to Lustig, at least 50 percent of Americans have some form of insulin resistance — whether you're overweight or not — and that is what's driving our seemingly out-of-control disease statistics.

'There Are More Thin Sick People Than Fat Sick People'

As Lustig notes, if you were to do a Venn diagram of the U.S. population, one circle would be about twice as big as the other: the obese population forming a smaller circle of about 30 percent, and the non-obese population forming a larger circle of about 70 percent.

He estimates that about 80 percent of the obese population is metabolically ill with insulin resistance that manifests itself in a myriad of ways, including type 2 diabetes, hypertension, dyslipidemia, heart disease, cancer and dementia. About 20 percent of this population, however, is metabolically healthy.

Conversely, Lustig explains, of the 70 percent that are of normal weight, about 40 percent of them have insulin resistance upon lab testing, and they manifest aspects of metabolic syndrome as well. They too get type 2 diabetes, hypertension, dyslipidemia, cardiovascular disease, cancer and dementia.

The prevalence of metabolic disease among normal-weight people is not as great as among obese people — 40 percent versus 80 percent — but there are far more people in this group.

"When you do the math, there are more thin sick people than there are fat sick people," Lustig says. And while his research points to excessive sugar consumption as the primary driver of metabolic disease among Americans, inactivity also plays a role.

Exercise Is Important, but Not Necessarily Because It Helps You Lose Weight

The evidence is clear that regular physical activity, which includes reducing your time spent sitting and exercising, is crucial to lower your risk of diabetes (and treat it if you've already been diagnosed).

For instance, sitting for more than eight hours a day has been shown to increase your risk of type 2 diabetes by 90 percent,7 while people with diabetes who engaged in a six-month moderate-intensity exercise program experienced significant health improvements, including decreased fat in the abdomen, liver and around the heart.8

Many health care professionals advise their patients to exercise in order to promote weight loss; however, its benefits extend far beyond that (which is why it's important to exercise even if you don't need to lose weight).

According to Lustig, one of exercise's primary benefits is that it promotes muscle gain and stimulates peroxisome proliferator-activated receptor-gamma coactivator 1 alpha (PGC-1 alpha), which is the primary driver for mitochondrial biogenesis.

When you turn up PGC-1α, you make more mitochondria, increasing your sympathetic muscle tone, which in turn improves insulin sensitivity. According to Lustig:

"Exercise is the single best thing you can do for yourself and we should be promoting it, but we have to explain to patients what the outcome variable they should be looking at is.

And the outcome variable is belt size [waist size], because they will reduce their visceral fat. They will lose inches, not pounds. And losing inches means improved metabolic health."

How to Determine if You're Pre-Diabetic

If you're reading this and aren't sure what your fasting insulin and glucose levels are, these are blood tests I recommend receiving annually. Your fasting insulin level reflects how healthy your blood glucose levels are over time.

A normal fasting blood insulin level is below 5, but ideally you'll want it below 3. A fasting glucose level below 100 mg/dl suggests you're not insulin resistant, while a level between 100 and 125 confirms you have pre-diabetes. If this, or your A1C level, confirms you either have or are at risk of pre-diabetes or diabetes, the time to take action is now. You might also find a hip-to-waist size index chart helpful.

This is far better than body mass index (BMI) for evaluating whether or not you may have a weight problem, as BMI fails to factor in both how muscular you are and your intra-abdominal fat mass (the dangerous visceral fat that accumulates around your inner organs), which is a potent indicator of insulin/leptin sensitivity and the associated health problems.

You Can Improve Your Insulin Sensitivity in Just Two Weeks

Fortunately, proper exercise and attention to diet can reverse the course of this disease, with benefits seen in as little as two weeks (and to some extent after just one exercise session).

For instance, unfit but otherwise healthy middle-aged adults were able to improve their insulin sensitivity and blood sugar regulation after just two weeks of interval training (three sessions per week).9 A follow-up study also found that interval training positively impacted insulin sensitivity.

The study involved people with full-blown type 2 diabetes, and just one interval training session was able to improve blood sugar regulation for the next 24 hours.10 You can actually reap much greater benefits by exercising in short, high-intensity bursts known as intervals than you can exercising for longer periods at a slower steady pace.

The high-intensity interval training (HIIT) approach I personally use and recommend is the Peak Fitness method, which consists of 30 seconds of maximum effort followed by 90 seconds of recuperation, for a total of eight repetitions. I also recommend super slow weight lifting for your resistance training.

Getting Up From Your Chair Is Also Important

When you hear the term sedentary, it's important to understand that exercising for 20 or 30 minutes a day, and then sitting for much of the rest, is not enough to pull you out of this category. Long hours spent sitting are linked to chronic diseases including diabetes, and this may be, in part, because it increases aging at the cellular level.

In a study of 64- to 95-year-old women, those who sat for more than 10 hours a day and got less than 40 minutes of moderate-to-vigorous physical activity had shorter telomeres and were, on average, eight years older, biologically speaking, than women who moved around more often.11

Every time a cell divides, the telomeres get shorter, which is why they're used as a measure of biological aging. Short telomeres have also been linked with chronic diseases such as cancer, heart disease and diabetes.

In addition, your body's ability to respond to insulin is affected by just one day of excess sitting, which leads your pancreas to produce increased amounts of insulin. Research published in Diabetologia also found that those who sat for the longest periods of time were twice as likely to have diabetes or heart disease, compared to those who sat the least.12 I recommend replacing the majority of your sedentary sitting time with active movement, keeping sitting to three hours a day or less.

What to Do if You Have Pre-Diabetes or Diabetes

The take-home message to remember is that you shouldn't assume you're metabolically healthy just because you're not overweight or obese — especially if you live a largely sedentary lifestyle. You could actually be "skinny fat," with many of the same health risks as someone who's overweight or obese and sedentary.

The good news is that there's plenty you can do to not only reduce your risk of type 2 diabetes and pre-diabetes but also improve your metabolic health at the same time.

During the three-year Diabetes Prevention Program study, for instance, lifestyle interventions were found to be more effective than the diabetes drug metformin at preventing or delaying the development of diabetes in people at high risk of the disease. A follow-up study monitored the group for 15 years — and lifestyle interventions were still more effective than metformin at preventing diabetes.13

After the initial three-year study, those who made dietary changes and exercised at moderate intensity for 15 minutes daily were 58 percent less likely to develop diabetes compared to a placebo group. Those taking metformin were 31 percent less likely to develop the disease. Nutrition and lifestyle modifications should be the foundation of your diabetes prevention and treatment plan.

Remember, this is about getting metabolically healthy, not necessarily losing weight, but optimizing your weight is a pleasant "side effect" that comes from a healthy lifestyle.

One of the most important dietary recommendations is to limit net carbs (total carbohydrates minus fiber) and protein, replacing them with higher amounts of high-quality healthy fats, like seeds, nuts, raw grass-fed butter, olives, avocado, coconut oil, organic pastured eggs and animal fats (including animal-based omega-3s).

If you're insulin resistant or diabetic, I also strongly suggest you limit your total fructose intake to 15 grams per day until your insulin/leptin resistance has resolved (then it can be increased to 25 grams) and start intermittent fasting as soon as possible.

As mentioned, exercise and reduced sitting time are also crucial, along with attention to proper sleep, optimized vitamin D levels and gut health. Taken together, this plan will lower your risk of diabetes and related chronic diseases and help you to avoid becoming victim to a health condition you might not even realize you have.

Should we consider skipping breakfast?

For years we have always been told that breakfast is the most important meal of the day.  It is the meal that jump starts our metabolism.

Where is all this evidence?

In a recent paper, published in the American Journal of Clinical Nutrition, researchers approached the breakfast question with a healthy dose of skepticism.

They analyzed dozens of studies looking at one particularly interesting relationship: breakfast and body weight. And asked the question: Is the evidence really that strong?

A little background first.

Many nutrition experts claim that breakfast is so important because it helps with weight management. (They also think that skipping breakfast leads to weight gain and obesity.)

Interestingly, it’s this supposed causal relationship between breakfast and body weight that forms a cornerstone belief of the “most important meal of the day” movement.

Unfortunately for this movement, the link is weak. And it’s correlational, not causal.

In essence, we know there’s some relationship between breakfast and body weight. But we don’t know what the relationship is. Or whether it’s important.

With that said, back to the study.

In analyzing dozens of individual papers — called a meta-analysis — the researchers concluded that the link between breakfast and body weight is “only presumed true.”

In other words, the idea that “breakfast is the most important meal of the day” is more of a “shared belief” than a research proven conclusion.

Here’s how it works.

Since we’ve heard it so often — heck, some of us have even said it — the phrase “breakfast is the most important meal of the day” becomes part of our cultural lexicon.

Then, because we believe in it culturally, any information that runs counter it is assumed to be wrong. Even before we evaluate the evidence.

Interestingly, according to this published research, it’s not just regular people who commit this error. Nutrition experts and researchers do the same thing.

In fact, when they really dug into the literature, they found four extremely serious problems:

1) researchers were offering biased interpretation of their own results,
2) researchers were improperly using causal language to describe their results,
3) researchers were misleadingly citing others’ results, and
4) researchers were improperly using causal language when citing others’ work.

All this to say that researchers aren’t immune to bias.

In fact, when it comes to the relationship between breakfast and body weight, many researchers are so committed to the shared belief that eating breakfast is the right thing to do that they — often unintentionally — misrepresent their results and the work of others.

How important is breakfast really?

Of course, we can’t throw the baby out with the bathwater here.

Just because some research is biased — or incomplete — doesn’t mean that it’s meaningless. So let’s start with some of the proposed benefits of eating breakfast.

In the literature, eating breakfast is consistently associated with:

· decreased overall appetite
· decreased overall food consumption
· decreased body weight
· improved academic performance
· improved blood sugar control

If we stopped there, of course we’d presume that breakfast skipping is a dumb move.

However, we can’t stop there. Because the majority of this evidence is observational. It suggests there’s a relationship — a correlation — without proving cause.

For example: It could be that people who are “healthy” for other reasons — like the fact that they work out more or benefit from a higher socioeconomic status — also eat breakfast. While those who are “unhealthy” — because they don’t exercise or live below the poverty line — skip it.

In this case, breakfast just happens to co-exist with health rather than cause it.

So here’s the bottom line: When examining research that actually controls for all the variables and looks at cause and effect, the results are pretty mixed.

In other words, breakfast looks to be beneficial for some of us. But not for others.

The strongest of this evidence suggests that breakfast is most important for malnourished or impoverished children. But, for other populations, it seems to bejust another meal. No better. No worse. Completely negotiable.

Are there benefits to skipping breakfast?

There’s also the new data showing that skipping breakfast might not be so bad after all.

Folks with Type 2 diabeties, for example, did better in this study when they skipped breakfast altogether and ate a larger lunch.

Other folks who were told to skip breakfast ended up eating less overall compared to breakfast eaters.

And skipping breakfast is also just as effective as eating breakfast for weight loss.

Of course, we can play dueling studies all day long. I can show a study suggesting one thing. You can find a study suggesting the opposite. And, in the end, when it comes to the value of breakfast, we’d be at a scientific stalemate.

Which is why I often look at what’s happening outside of the literature.

The breakfast skipping movement.

In the popular media and across the web, an interesting breakfast counter-culture is cropping up. A virtual army of people intentionally skipping breakfast are sharing a host of health benefits they’ve experienced since getting rid of their morning meal.

This movement is part of a larger one known as intermittent fasting; the most popular form involves skipping breakfast each day, extending the overnight fast from dinner the night before until lunch the next day.

There are other types of fasting that involve even longer fasts each day, extending the overnight fast from dinner the night before to dinner the next day. And other types that even suggest skipping meals for one or two entire days each week.

And the reported health effects of an intelligently designed intermittent fasting program read like a laundry list of live longer, live better benefits including:

blood lipids, blood pressure, markers of inflammation, oxidative stress, and cancer

Cell turnover and repair, fat burning, growth hormone release, and metabolic rate

Appetite control, blood sugar control, cardiovascular function, and neuronal plasticity

And, yes, many experts believe that skipping breakfast is part of the magic here.

(To read more about intermittent fasting, including a review of the most popular types and a summary of my own personal experiments, click here.)

So, will skipping breakfast be better for me?

Maybe yes. Maybe no.

Preliminary evidence suggests that skipping breakfast can:

· increase fat breakdown
· increase the release of growth hormone (which has anti-aging and fat loss benefits)
· improve blood glucose control
· improve cardiovascular function
· decrease food intake

However, the truth is, most of this research has been done in animals, with only a few conclusive human studies. So, while intriguing, there’s certainly no guarantee that these changes in our physiology will actually lead to long-term benefits.

In fact, many times, immediate changes are corrected for, and balanced out, later. That’s why acute changes don’t always lead to chronic ones.

Also, anecdotally, skipping breakfast seems to be a mixed bag.

Many report great results from skipping breakfast and having fewer, but larger, meals each day. Others report that it provides no benefit. Yet others report some really negative effects, such as decreased energy, lack of focus, and disrupted sleep.

Clearly eating breakfast — or skipping it — is not a panacea. Of course, no nutritional solution ever is.

What to do now.

The take-home message here is pretty simple: Breakfast is optional.

(Which means it’s not “the most important meal of the day.”)

  • If you love breakfast, are doing well with eating it, and feel like it’s helping you accomplish your health and/or fitness goals: Keep at it!
  • If you’re not a breakfast person, function really well without it, and are accomplishing your health and/or fitness goals: there’s no harm in waiting until later.

Of course, I’d also be remiss if I didn’t remind you that  matters too. But that’s another topic for another day.

By: John Berardi, Ph.D.