Tag Archive for: body fat

BRI: It Just Doesn’t Matter

/in /by

Continuing our look at the BRI, the mathematician demonstrated that BRI is associated with body fat distribution. It makes sense; the waist measurement would provide an indication of fat around the waist. The next question is: would the BRI be a better predictor for cardiometabolic disorders than BMI?

BRI and Mortality

A group of researchers decided to use open-source data from the National Health and Nutrition Examination Survey database to examine the relationship between BRI and all-cause mortality. They coincided with the years that physical assessments were done including height and waist circumference; body weight was collected but not used in this instance. The time period began in 1999 and continued every two years through 2018.

There were two observations that were significant. First, in every demographic group, regardless of age, gender, or race/ethnicity, the BRI has increased during every examination period. As a country, the U.S. has gotten fatter. That matches every other measure such as body weight or BMI as well.

The second observation was that the hazard ratio (HR) increased as the BRI dropped below normal, then normalized when the normal BRI was reached, and the HR rose again as the BRI increased. Simply stated, there was an increased risk of mortality when people were too lean or too fat.

You may be wondering why I don’t give you a formula to do calculations for yourself. It’s very complicated and there are BRI calculators available on the website below. The main reason is that it just doesn’t matter—the BRI is no better at predicting mortality than the BMI. The researchers had the body weight data they needed to compare the BRI with the BMI directly. They just didn’t do it. However, looking at the mathematicians’ validation study, the categories of adiposity associated with BMI matches up quite well with the BRI and thus with body fatness. There’s no need for any more precision than is achieved with BMI.

The Bottom Line

It’s really the clinical use that seems to bother everyone, but with rare exceptions, the BMI gives an indication of body fatness. If physicians or other health care professionals cannot see the patient before them and realize they are too lean or too muscular to fit the typical interpretation of BMI, the fault lies with them, not the tool they are using.   

What are you prepared to do today?

        Dr. Chet

References:
1. JAMA. 2024; 332(16):1317-1318. 10.1001/jama.2024.20115
2. JAMA Netw Open. 2024; 7(6):e2415051. 10.1001/jamanetworkopen.2024.15051.
3. https://doi.org/10.1002/oby.20408
4. https://bri-calculator.com/#calculator

Body Roundness Index

/in /by

The Body Mass Index (BMI) has been used to provide an indication of whether someone is under weight, normal weight, overweight, or obese and the degree to which they are obese. There’s no measure of percentage of body fatness implied, but physicians and other medical professionals have used it for that purpose for a couple of decades. Why? It can be used to assess the potential risk of developing cardiovascular disease, pre-diabetes, and other metabolic conditions.

I happened upon a commentary in JAMA on the Body Roundness Index or BRI for short. It was published in response to a recent study published in a JAMA Network Open by researchers who examined the relationship between BRI and mortality.

Let’s start with this: what is the BRI? The BRI was developed by a mathematician. The reason was interesting; the developer told the commentator that the BMI is based on a “cylindrical” model but when she looked in the mirror, she felt she was more egg shaped. What she did, as a mathematician, was develop a model based on an “ellipse.” Why? She gave a couple of reasons.

The first reason is that BMI can misclassify individuals because it fails to distinguish between individual amounts of fat-free mass (FFM) and fat mass (FM). BMI also does not provide information about the distribution of body fat—specifically, visceral fat versus subcutaneous fat. She developed a mathematical model, to assess body fatness which would indicate where the fat is distributed. With some very complicated math, she developed the BRI. It uses only two measurements: height and waist circumference. The benefit of using the BRI is that it may be a better predictor of body fat than the BMI. Is it? We’ll check out the research study that began this examination of BRI on Saturday, because as Shaq famously said about getting in shape, “Round is a shape.”

The Insider Conference Call is tomorrow night. If you become an Insider by 8 p.m., you can participate in the call to get your questions answered.

What are you prepared to do today?

        Dr. Chet

References:
1. JAMA. 2024; 332(16):1317-1318. 10.1001/jama.2024.20115
2. JAMA Netw Open. 2024; 7(6):e2415051. 10.1001/jamanetworkopen.2024.15051.
3. https://doi.org/10.1002/oby.20408

How the Quality of Your Diet Changes Your Mycobiome

/in /by

In the experiment I told you about on Tuesday, the researchers established that environment—exposure to light, temperature, and other environmental factors—affects the microbiome, including the fungi or mycobiome. The researchers then tested the changes in the mycobiome (the fungus part of the microbiome) after feeding the mice a highly processed diet compared with mice eating conventional mice chow. They also monitored changes in body composition, triglycerides, and other hormones related to obesity.

After eight weeks on the highly processed diet, there were differences in the quantity of fungi. Some groups of related organisms increased while others decreased. Because not every group has known roles in digestion and metabolism, the researchers examined metabolic changes in response to the dietary change; they found an increase in body fat and triglycerides in the male mice along with concurrent changes in hormones that signified a move toward prediabetes. (For some reason, the female mice in this species are protected from those effects.)

After examining the composition of the highly processed chow, I’d like to have seen one more group of mice in the experimental group. Because the highly processed chow had no fiber, it would have been helpful to see what would happen to the entire microbiome if the amount of fiber was the same in the processed chow as the conventional chow. Maybe it wouldn’t have impacted the fungi at all, or the change could have been significant.

The Bottom Line

What lessons can we learn from this study? We’re not mice after all. I think it means that a highly processed, highly-refined carbohydrate diet may cause undesirable changes in our microbiome, including the fungal levels as well. For example, Candida albicans is a primary fungus in our digestive system, but it can cause all kinds of problems if it gets out of control. Reducing refined carbohydrates has a beneficial impact on keeping that fungus at beneficial levels.

Regardless of your current age, a better diet is part of Aging with a Vengeance. Reducing processed food, especially carbohydrates, can benefit your microbiome and all that it impacts. Time to start now.

What are you prepared to do today?

        Dr. Chet

Reference: Comm Bio (2021).4:281 https://doi.org/10.1038/s42003-021-01820-z

Planning Your Infrastructure Upgrade

/in /by

In order to give you some ideas to help you focus on your body’s infrastructure, I’m going to share my list. I’ll give you my issues and why I feel they’re problems for me; I hope that will stimulate your thinking so you can determine your infrastructure upgrades for 2021. I don’t know that I can accomplish all of them in a single year, but I do know I can make a good start, and that’s what I’m hoping you will do as well.

Increase Muscle Mass

If there’s one getting-older issue that I completely underestimated, it’s the loss of muscle mass. It just sort of crept up on me and while I can’t quantify it in terms of pounds or percentage, I know I’ve lost strength in my upper body, and my legs seem to be a shadow of their former selves. Part of the reason that my legs lost so much mass, I believe, is directly tied to my inability to run consistently. I have no idea when I’ll be able to run freely again, if ever, so strength training is going to be critical to increase strength if not mass.

Improve Skin Quality

I have to confess that I never examine my skin. I don’t spend a lot of time looking at my face in the mirror, and I ignore my arms completely. But lately I’ve noticed that my skin is thinner and a slight scrape against the door frame that doesn’t even hurt can leave a huge purple spot. I’m not trying to recreate the quality of skin I had in my 20s, but I know it can be better than it is. (Has anyone in my household been nagging me about this for years? Um, maybe.)

Decrease Body Fat

The one that drives me crazy is the increase in body fat around my waist. I weigh 45 pounds less than my highest body weight ever, yet my waist circumference is greater now than it was then. The reasons are complicated, from the loss of muscle mass reducing metabolic rate to the gradual reduction in hormones as I get older. I know that there’s no such thing as spot reduction, and I don’t know if the general rule “you lose it first from where you put it on last” applies as you get older. But aside from increasing muscle mass, this one is just not acceptable and is a priority for me.

Increase Bone Mass

I’ve made no secret of the fact that I have osteopenia. In fact, I’m one-tenth of a Z-score from having osteoporosis. I have improved my vitamin D and calcium intake since my last bone-density test. I’ll find out in April whether that has resulted in any change. I’m not interested in continuing to be the amazing shrinking man, so this is an internal infrastructure change that must happen in 2021.

Improve Posture and Balance

This one seems a lot less obvious, but it’s still critical to overall health. Why? Because working on improving posture now, which means resetting the resting “tone” of the postural muscles will help with balance as we get older, and balance is critical if we hope to make it to an advanced age. The inner ear is part of it, but our ability to be able to move and do the things that we want to do can be dramatically impacted by poor balance. The modifications in muscle mass and fat mass, as well as bone mass, will have an impact, but it’s also critical to specifically work on posture and balance movements as well.

The Bottom Line

There you have it: my infrastructure plan for 2021. I’ve begun working on some, but there’s still research to read to find better solutions. That will include different approaches to exercise, whether weight training, stretching, or aerobic exercise. There could be specific dietary approaches that apply rather than just cutting calories. Supplementing with nutrient isolates and specific dietary supplements may also be part of the solution.

How about you? You may have cholesterol and HbA1c that needs to get lowered, cardiac output that needs to increase, and a microbiome overhaul; maybe you need to build strength in specific areas to compensate for arthritis and loss of cartilage.

Identify your three to five areas and write them down. As the year progresses, I’ll share the solutions I’ve found with you because my goal hasn’t changed: to help you become the best version of yourself. Specify where you want to go and let’s get started.

What are you prepared to do today?

        Dr. Chet

Health Habits: Just Do Better

/in /by

Let’s finish up our look at the recent paper that concluded we’re doing poorly when it comes to our health habits (1). If you thought smoking and exercise were underwhelming, today we’ll look at diet and body fat.

When it comes to following the U.S. Department of Agriculture Dietary Guidelines, just under 38% hit that goal. I’ve talked about this a lot over the years, and this isn’t a debate over what constitutes a good diet. While we are doing somewhat better, adults do not eat enough vegetables, fruits, or beans, and we still . . .

We're sorry, but this content is available to Members and Insiders only.

If you're already a DrChet.com Member or Insider, click on the Membership Login link on the top menu. Members may upgrade to Insider by going to the Store and clicking Membership; your membership fee will be prorated automatically.

The Cause of Obesity: The Lack of Exercise

/in /by

After reading Thursday’s message, I’ll bet you all saw this one coming. Together with taking in too many calories, we just move way too little and it costs us. I specifically made the title of Thursday’s message “Muscle Aging” instead of “Aging Muscle.” The reason is that our sedentary lifestyle causes the muscle to age faster than it should. The solution is exercise. Here’s a partial list of what exercise does for skeletal muscle:


Better Blood Flow

Regular exercise increases blood flow to the exercising muscles. That allows nutrients in and more important, waste . . .

We're sorry, but this content is available to Members and Insiders only.

If you're already a DrChet.com Member or Insider, click on the Membership Login link on the top menu. Members may upgrade to Insider by going to the Store and clicking Membership; your membership fee will be prorated automatically.

The Cause of Obesity: Muscle Aging

/in /by

In the previous message, I said that there was one factor besides calorie intake that affected the rate of obesity in the United States. Because a picture is worth a thousand words, just take a look at the CT scans at right (1). These are scans of the thighs of a 25-year-old man and an 81-year-old man, matched for body weight and height. There are a couple of things that you can notice. The white area is the muscle and the dark area is mostly fat; the older man’s thigh has visibly less muscle mass . . .

We're sorry, but this content is available to Members and Insiders only.

If you're already a DrChet.com Member or Insider, click on the Membership Login link on the top menu. Members may upgrade to Insider by going to the Store and clicking Membership; your membership fee will be prorated automatically.