In my day to day endocrinology practice one of the first complaints I hear from people, no matter what the medical problem, is about weight. Almost always, it is either because they are gaining or unable to lose it. When I began my medical practice 40 years ago, this was also the case. What is it about weight that prevents more progress from being made? Could it be because in nature having adequate amounts of stored fat on the body eg belly fat, is essential for survival in the same way having gasoline in the fuel tank of a car is needed to keep it going? Not to mention the role of fat as an insulator against the cold. Imagine trying to live through a winter without clothes, the way primitive humans did? Being covered in fat was literally a lifesaver. The more we know about the role of fat (adipose) in our lives the better we are equipped to live with (and without) it.
It’s tempting to think that all fat is built the same, but this is not true.
There are actually three types of fat; white, brown, and beige fat, and they are distributed in different parts of the body in different proportions, as either visceral fat (inside the body and organs) or subcutaneous fat (under the skin).
White fat is the fat most people are familiar with – over 73.2% of all Americans carry too much and are classed as either overweight or obese (CDC, 2017 to 2018). While some white fat is absolutely essential for a healthy metabolism, every body has its limits.
Brown fat is found mainly in babies and plays a key role in providing energy and keeping us warm. Adults retain a small percentage of brown fat around their necks and shoulders.
Beige, or brite fat, is similar to brown fat and is optimized for burning fat rather than storing it, unlike white fat.
As we can see, white fat is the ‘bad stuff,’ and is the type of fat that many of us worry about.
Visceral and Subcutaneous Fat
Fat is distributed as either visceral or subcutaneous fat, and there is a big difference between the two.
Subcutaneous Fat
Subcutaneous fat is stored under the skin in the limbs and extremities; arms, belly, thighs, and buttocks. When you pinch your arm or leg, you’re likely feeling a layer of subcutaneous fat distributed under the skin. Made up of mostly white fat, some subcutaneous fat is essential for hormonal function, as well as keeping warm.
While people with different body compositions will likely carry different percentages of subcutaneous fat, everyone has their limits. Subcutaneous fat is not totally harmless, but it poses fewer risks than visceral fat.
Visceral Fat
Visceral fat is stored primarily around and inside the abdomen. Yes – fat is more than skin deep and is stored inside of us as well as under our skin.
Whilst excess subcutaneous fat is still unhealthy, many recent and reputable studies such as this large-scale meta-analysis of 2.5 million participants suggest that visceral fat poses a much greater health risk than subcutaneous fat.
The increased health risk of visceral fat is linked to its proximity to the vital organs.
The closer fat is to the stomach and abdomen, the greater the chance is that it penetrates under the skin, wrapping itself around the liver, heart, kidneys, pancreas, and other organs. A study conducted by the University of Chicago and published in 2016 also found that visceral fat behaves differently from subcutaneous fat and resists fat burning (lipolysis). This also explains why abdominal fat is seen as ‘stubborn fat’ that is hard to lose.
Around 59% of all US adults were abdominally obese in 2015 to 2016, representing a massive increase from around 47% in 1999 to 2000 (CDC, 2016).
Visceral fat poses a much greater risk than subcutaneous fat in developing in the following conditions:
Heart disease
Type 2 diabetes
Insulin resistance
High blood pressure
High cholesterol
Certain types of cancer, such as stomach cancer, bowel cancer, pancreatic cancer and liver cancer
How to Measure Visceral Fat
Traditionally, BMI (body mass index) has been the go-to yardstick for measuring body fat. Today, many health authorities encourage the use of both BMI and abdominal fat measurements. The measurement of waist circumference is a popular method to assess abdominal fat. It’s possible to have a healthy BMI and high waist measurement, and vice-versa.
Take your shoes off and stand with your feet together.
With a bare stomach, relax and exhale all air from your diaphragm.
Use a fabric tape measure to measure your waist circumference at the naval.
Record the measurement.
Be aware that this measurement is likely not the same as what many consider to be their ‘waist’ measure (i.e. the measurement they use to fit trousers).
Men
Women
Low Risk
37 inches and below
31.5 inches and below
Medium Risk
37.1 to 39.9 inches
31.6 to 34.9 inches
High Risk
40 inches and above
35 inches and above
Does Abdominal or Visceral Fat Increase With Age?
The short answer is yes, it does. The plight of the so-called beer belly or middle-age spread is real!
This study published in the International Journal of Body Composition Research found that visceral fat increased by over 200% in men and 400% in women between the age of 30 and 70.
Why?
As we age, our metabolism changes and slows down, but the ‘middle-age spread’ is also linked to changes in behavior and diet.
To briefly summarize, aging reduces our percentage of lean muscle mass, which lowers our metabolic rate. Additionally, whilst it’s perhaps natural to indulge a little more as we get older, it’s easy to eat more and exercise less. That gives your body every excuse to pile on that abdominal fat!
Abdominal Fat and Menopause
Studies have shown that estrogen plays a major role in body fat distribution, hence why women experience a much greater change in visceral fat with age due to menopause accompanied by the loss of estrogen (400% vs 200% in men between the ages of 30 and 70).
Multiple studies, including this one published in the Journal of Menopausal Medicine, have also found that estrogen replacement therapy (ERT) can mitigate some of this weight gain. However, estrogen replacement is not without its risks and is unsuitable for many.
Namely, ERT can increase the risk of blood clots leading to strokes and embolisms and cause headaches, swelling, or edema. ERT is also often linked to an increased risk of breast and ovarian cancer. It is worth mentioning however, studies reviewed by Breastcancer.org show that the risk is only significant after using ERT 10 years or more (in the case of estrogen-only therapy). Combination HRT which includes both estrogen and progesterone poses a much greater risk.
As such, ERT is certainly not a ‘silver bullet’ for treating menopause-related abdominal weight gain.
Part 2 of this article will be published in 2 weeks at this website www.metabolism.com
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What is Metabolism and How Does It Change with Age?
By Gary M. Pepper, M.D. and Sam Jeans, MSc
Our bodies undergo many transitions as we age, some good and some not so good!
In the latter category of “not so good”, many people tend to struggle more with their weight as they get older. Obesity rates are higher in older populations, and in the United States, more than 30% of both men and women over 60 are obese.
Obesity in older age brings about much of the same risks as it does at any age, including an increased risk of heart disease, diabetes, high blood pressure, stroke, and mobility problems, and the risks climb ever higher with each year that goes by!
Unraveling what happens to our metabolism as we age helps provide strategies for staying healthy and reducing the risks of putting on excess weight. The popular consensus is that, as we age, our bodies ‘slow down’, which makes it tougher to keep weight off, but does that really tell the whole story?
Metabolism Defined
At its most fundamental, metabolism encompasses every chemical process required to sustain life. It’s easy to confuse the entire concept of metabolism with just the basal metabolic rate (BMR) alone, but this is just one component of metabolism.
Many people use the terms interchangeably, whereas, in fact, there are three main components to metabolism:
1: The Basal Metabolic Rate (BMR)
The body is in constant motion, so even when we’re totally sedentary, sleeping, or otherwise at rest, we require energy and nutrients to function correctly.
So long as the heart pumps, the lungs breathe and the body and its organs go about their business growing and repairing cells, we are utilizing energy in one form or another, and this is our basal metabolic rate (BMR).
The BMR varies depending on the following factors:
Body Size and Muscle: Larger bodies have greater energy demands and higher BMRs.
Lean Muscle Tissue: Whilst it’s true that larger bodies have greater energy demands, BMR also increases relative to the proportion of the body that is made up of lean muscle. Muscle burns more energy than most other tissues.
Body Fat Percentage: Fat burns energy at a much lesser rate than most cells. A high body fat percentage relative to lean muscle tissue results in a lower BMR, even if the body itself is physically larger.
Age: Age does affect the BMR for a few different reasons, which we will discuss shortly.
Growth: Younger children have generally higher BMRs due to body growth, and they also need more energy to maintain their body temperatures.
Gender: Men likely have higher BMRs than women on average as they’re larger and have higher percentages of lean muscle tissue.
Genetics: Genetics do play a role in BMR, but there is debate surrounding quite how drastic the influence of genetics is compared to other factors.
Hormones: Hormone levels, particularly those governed by the thyroid gland, also influence BMR. Hypothyroidism (sluggish thyroid function) is associated with a lower BMR whereas hyperthyroidism (excessive thyroid function) is associated with elevated BMR. Metabolism-related hormones are also influenced by diet, for example, iodine deficiency may result in an underactive thyroid that lowers BMR.
Activity Level: Whilst physical activity burns energy directly as a result of exercise, it also raises BMR by stimulating the growth and repair of new cells, such as muscle cells.
Infection: Infections stimulate an immune response that requires energy, thus boosting BMR.
Environment/Temperature: Colder environments may increase BMR slightly as our bodies work harder to maintain a stable core temperature. Conversely, hotter environments may increase BMR as our bodies work harder to cool down.
2: Thermic Effect of Food (TEF)
The consumption of food itself requires energy and some foods are much easier to digest than others.
It takes considerable effort for our bodies to move food through the digestive system, and our body also needs to absorb and transport nutrients from that food, which further requires energy.
A concept that tends to pop up in various diet plans is ‘calorie negative food’ – that is food that burns more calories to digest than they provide as food. Sadly, there is no evidence that we can ‘eat ourselves thin’ by consuming calorie-negative food!
TEF varies considerably depending on the food consumed and its macronutrients content:
Fat has a thermic effect of some 0 to 5%, which means that for every 100 calories of fat consumed, the body burns just 0 to 5 calories
Carbohydrates have a thermic effect of around 5 to 10%, so for every 100 calories of carbs consumed, the body burns just 5 to 10 calories.
Protein has a much higher thermic effect of around 20 to 30%, so for every 100 calories of protein consumed, the body burns 30 calories (Source: Healthline).
Thirdly, our body requires energy to sustain movement and exercise. This is highly variable and obviously depends on physical activity levels – the more we move, the more energy we require to breathe, fuel our muscles, and repair cells.
Common estimates suggest that physical exercise uses between 15% and 30% of average daily energy expenditure. Engaging in intense or protracted physical exercise ( such as running a marathon) will increase that figure.
The total accumulative energy required for these 3 metabolic components – BMR, TEF, and TEE, makes up our total daily energy expenditure.
In Part 2 of this article, we will cover how aging affects our metabolism and what we can do about it. Check back at metabolism.com for the publication date.
Disclaimer: This and all articles at www.metabolism.com are for educational purposes only and are not intended as medical advice or treatment. By choosing to view this article you agree to the Terms of Use of Metabolink, Inc which can be found at https://metabolism.com/terms-of-service-and-our-privacy-policy/
When kids come up against that common eat right and exercise refrain, they may be all too apt to brush health concerns aside as something only adults have to consider. Heart issues, kidney problems, and especially type 2 diabetes — those words have an “adults only” connotation.
However, the potential to develop type 2 diabetes in adulthood or even earlier comes with a clear link to overweight and obesity at young ages. With it comes an elevated risk for associated health complications, too. While research has indicated some alarming trends, there are also promising findings that hint at the opportunity for individuals to make sustainable change.
Sustainable change isn’t about simple calorie counting — where those calories come from can have just as big an impact on overall health. Families can have fun experimenting with recipes and food choices to give kids the power to view nutrition as a holistic part of their everyday routine.
Prediabetes and Type 2 Diabetes Cases on the Rise
Type 2 diabetes, a disease once known as adult-onset diabetes, has started to impact young people more and more. Recent research paints an increasingly unsettling picture.
But it’s not just prediabetes acting as a glimpse of a problematic but distant future. Researchers are also seeing a shift in type 2 diabetes prevalence in youths. A CDC report from 2020, for example, found the rate of new type 2 diabetes cases for young people under 20 years old in the United States increasing 4.8% per year.
Obesity and Overweight As Diabetes Risk Factors
Though not the only factors, obesity and overweight are helping to spur the rise in type 2 diabetes among children and adolescents. A 2005 review in the journal Pediatricsexamined the ongoing trend. The review noted that having overweight or obesity actually serves as the biggest risk factor for youth to develop type 2 diabetes, highlighting weight loss and prevention of weight gain as strategies to combat eventual disease development.
Indeed, as the number of overweight and obese children has increased, so too has the number of type 2 diabetes cases in younger people. Early diabetes development means affected young people may start experiencing complications associated with diabetes at an earlier age as well.
What Happens When Young People Develop Type 2 Diabetes?
Younger diabetes diagnosis and the potential for complications at an earlier age speak to the heart of the looming public health problem.
An earlier type 2 diabetes diagnosis goes hand in hand with greater risk. Earlier development means longer exposure to the disease, and young people who develop type 2 diabetes may need treatments like insulin earlier in life. Evidence also exists hinting at early-onset type 2 diabetes as a more aggressive form of the disease.
Children and adolescents with type 2 diabetes face health issues similar to their adult counterparts, but may experience these complications starting at an earlier age, according to the review in Pediatrics. Cardiovascular complications, kidney issues, health problems that threaten the limbs — the list goes on. Even if the diabetes diagnosis doesn’t come during childhood or adolescence, kids who are overweight or obese are still at a higher risk to develop the disease eventually.
Research Highlights Promising Opportunities for Change
The news isn’t all bad, though. Consider a study by Bjerregaard et al published in the New England Journal of Medicine in 2018.
Acknowledging that children who have overweight are at an increased risk for type 2 diabetes in adulthood, the study looked at Danish men who had their weights and heights measured at 7 and 13 years old and then again in early adulthood, defined in the study as between the ages of 17 and 26. The researchers sought to determine if children who were overweight at a young age would continue to have an increased risk of developing adult type 2 diabetes if they no longer were overweight at puberty or later.
The study uncovered promising statistics. Men who maintained a normal weight in early adulthood after losing weight between 7 and 13 years old had a risk of type 2 diabetes similar to men who had normal weight at all ages. While men who lost weight between 13 years old and early adulthood had a higher diabetes risk than men who had never been overweight, the risk was still lower than in men who were overweight at all ages included in the study.
Reversing the Trend Starts At Home
Focusing on being overweight in puberty as an important factor ultimately increasing the risk of developing type 2 diabetes later in life, the New England Journal of Medicine study indicates just how important learning healthy habits at a young age can be.
Family factors — such as food available at home and food preferences of family members — can influence what kids eat, and these factors have been associated with rising obesity cases. On the flip side, if kids learn about healthy eating, positive nutritional choices, and exercising at home, those lessons can carry over into choices kids make beyond the walls of their home.
Being overweight or obese aren’t the only risk factors for developing type 2 diabetes, and a holistic, empowering approach to any weight loss recommendations for kids is certainly a must. Still, the clear link means it’s something kids and the adults in their lives should pay attention to. Type 2 diabetes comes with the potential for complications in childhood and beyond — and the risks only increase with earlier disease onset. Yes, the stakes are high, but research indicates the lasting, positive impact that changes to nutrition and activity can have
Weight management is a key component of a healthy lifestyle although keeping one’s weight on track is often a frustrating and perplexing task. To get the whole family involved in the weight management effort may seem almost impossible.
Simply identifying a younger member of the family as overweight can be a challenge.
A 2015 study from the U.K. found that 31% of parents underestimated their child’s weight status. For a child who is “very overweight†per government guidelines there was an 80% chance the parent would classify the child as healthy weight. Teens themselves are not very good at identifying themselves as overweight as 80% of overweight teenaged boys and 71% of overweight teenaged girls perceived themselves as normal weight. Recognizing that a child is overweight is crucial to preventing the progression to adult obesity. 72% of overweight kindergartners were obese by the time they reached 8th grade. (more…)
Many members here at metabolism.com have shared their thoughts and experience on ways to stop smoking. There have been many who feel defeated because they can’t beat the weight gain that accompanies their efforts. SweetiePie has a clear message about how not to beat yourself up while achieving the goal of a smoke free (and healthier) life.
Here’s what SweetiePie has to say;
Hello:
55 Year old female here, 200 lbs, hypothyroid smoke free for 6 months. Feeling great about being smoke free and this time its permanent and for real.
I have quit smoking and relapsed so many times in my life. And dieting, on again and off again for 40 years. Pfffft…..This time what prompted me to go to the doctor and quit was that my heart feels heavy and hurts sometimes. Not angina yet, but scary and depressing. I’m fine, it turns out, but I definitely needed to quit smoking and still need to exercise more and lose weight . I am no expert in the weight loss department, having had limited success with that over the years. I can see from this interesting thread that I am not as weight conscious as most of you, but I still thought I’d share what my doctors told me because it may help and inspire you the way it did to me: When I tried to bring up the weight gain and the overweight with doctors heres what they said: CARDIOLOGIST told me I’d have to be about 100 lbs over my ideal weight of 145 for the weight to be as stressful and damaging on my heart and cardiovascular as SMOKING, GP #1 told me the key was, instead of focusing on an ideal weight and size, was to focus on preventing DIABETES through NONSMOKING, AND EXERCISE just as important as wholesome diet, and GP #2 (I moved and needed a new doctor for my thyroid perscription) told me, after my bloodwork tested all ok, “why don’t you just forget about losing weight for a little while and focus on quitting SMOKING? Well, I took all of that advice, and this time, it worked! I’ve really kicked the smoking habit and finally found freedom from that deadly addiction. The “permission†from doctors to stop beating myself up about my weight freed me up mentally to do what I needed to do (giving myself plenty of rewards, including food treats and being lazy treats!) in order to become smoke free and never going back! I am ready now to step up to exercise and weight loss this year with the same strategy: Increased exercise first, food modification instead of deprivation. The reason for my post is to say stick with it but your QUIT is SO IMPORTANT – don’t ever let your desire to be thinner or to get back down to an ideal outweigh your resolve to stay SMOKE FREE. SMOKING is the singlemost damaging behavior -don’t lose sight of that! Never take another puff! Oh, btw I gained about 5% while quitting and my first goal is to go back down 5%.
The mission of the The Thyroid Project is to encourage sharing of information and experience between the public and the medical community about the treatment of hypothyroidism (low thyroid function). For at least the past few decades there is a growing awareness of “something missing†in the way suffers of hypothyroidism are treated for their disease.
Too many patients, as documented in an on-line study of 12,000 individuals conducted by the American Thyroid Association published in June 2018, (https://doi.org/10.1089/thy.2017.0681) , complain of persistent symptoms of hypothyroidism despite what their doctors believe is successful treatment with levothyroxine (brands include Synthroid, Unithroid, Tirosent, Levoxl). We believe something needs to be done to resolve this conflict between patients and their doctors.
Without effective intervention the early stage of type 2 diabetes known as prediabetes carries a high risk of progressing to outright diabetes. Metabolism.com provides an up-to-date summary of recommendations from national authorities, for preventing and possibly reversing this life long affliction
Diabetes can be defined simply as elevated blood sugar levels. What exactly is high blood sugar and when should someone be concerned about their level? Does having prediabetes mean diabetes is around the corner? Metabolism.com tackles this tricky but important topic in this comprehensive review.
By Gary M. Pepper, M.D. Ozempic, Rybelsus, Trulicity, Wegovy, Saxenda are the central players in the weight loss craze sweeping across the globe. Metabolisim.com has been monitoring this phenomenon from its beginnings in 2008 with its report “Lizard Spit Reduces Blood Sugar and Appetite”, regarding the first drug in this class, Byetta (exenatide). Caught In the middle of the current chaos are the medical experts who treat diabetes and have been prescribing these medications for more than a decade. Here is a brief commentary from one such board certified endocrinologist; “I started treating Type 2 diabetics with GLP-1 agonists more than 10 years ago. In some respects, these medications have revolutionized the treatment of diabetes by lowering blood sugar effectively and promoting weight loss at the same time, a unique combination of benefits. Not everyone benefits from these drugs to the same degree unfortunately, and I have seen lots of patients experience unacceptable side effects from them. Nothing though, has prepared me for what is happening now. Too often, I find myself confronting someone who expects me to prescribe one of these drugs just so they can lose weight. Sadly, one extreme example was someone who, despite battling a life threatening medical condition, was insistent on getting a prescription. At the same time my diabetic patients are scrambling to find a place to buy their medications if they can even afford it. It is disheartening, to say the least, and I dread the negative interactions with some of my patients I now face almost daily.”
Off- Label Use
The FDA is the U.S. government’s department tasked with evaluating and approving drugs for specific medical conditions. When a new medication is approved for treating a medical condition by the FDA the agency will, at the same time, set strict guidelines for exactly which patients may use the newly approved drug. When a medication is used “off-label” it means that these limitations are being overridden by the provider for a potential benefit which outweighs the drugs risks. It is a general misconception that off-label means illegal; it does not. This practice has been going on for ages and more than 20% of prescriptions in the United States are prescribed off-label. A common example is the use of beta-blockers (approved for heart problems) for the treatment of performance anxiety.
GLP-1 agonist drugs, as discussed recently by metabolism.com. were originally approved for the treatment of Type 2 diabetes in adults. In the past few years most of these same medications have gained unprecedented popularity for their “off-label” weight loss benefit. Of the 5 GLP-1 agents presently in U.S. pharmacies only Wegovy (semaglutide) and Saxenda (liraglutide) are FDA approved for treating obesity. Of these two, Wegovy is the newer and had been much more popular that its sister drug Saxenda, probably due to being dosed only once weekly compared to daily for Saxenda and less likely to cause side effects. Due to Wegovy’s soaring popularity, its manufacturer, Novo Nordisk, increased the price of Wegovy two times since its initial release.
