KNOW YOUR FAT…………………YOUR BODY’S FAT!

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I know what many of you are thinking. Oh no! Not another post on “good fats” and “bad fats”, how saturated fat is NOT KILLING you! No, this post is not about dietary fat. I am talking about your body’s natural fat and how your body’s fat distribution decides your health.

Body fat or adipose tissue is not just a mass of fatty material lying around as inert weight. Without going into much details I will summarise a few important features.

  • There are different types of adipocytes that are broadly classified into white, brown, or beige adipocytes.
  • White adipocytes help store energy,
  • Brown adipocytes help in generating body heat (thermogenesis)
  • The function and origin of beige cells is less clear and is under investigation.
  • Adipocytes are recognized as critical regulators of whole-body metabolism.The major ones being lipid metabolism, blood sugar control, regulation of blood pressure, blood clotting and inflammation.
  • Insulin resistance. (More on insulin resistance in other post/video)
  • Fat cells secrete hormones that regulate energy homeostasis in other tissues. Leptin, Adiponectin and Resistin are the important ones.
  • Adipocytes secrete inflammatory substances called adipokines. There are about 50 known ones that are secreted by fat cells.
  • Adipocytes are involved in sex hormone metabolism through the enzyme aromatase. (This is very important in deciding you risk for breast and prostate cancers).
  • Hormone disrupting chemicals (EDC) ,environmental toxins are stored in fat (and they also increase fat store).

WHERE IS THIS FAT (ADIPOSE TISSUE) LOCATED?

Although the amount of total body fat is strongly associated with insulin resistance,heart disease, stroke, diabetes, cancer and dementia,it is becoming increasingly clear that different fat compartments contribute differentially to these risks.

From:Fuster, José J., et al. "Obesity-induced changes in adipose tissue microenvironment and their impact on cardiovascular disease." Circulation research 118.11 (2016): 1786-1807.

Brown Adipose Tissue: This is present mostly around the neck and its main function is in generating  body heat. Newborn babies have more of this fat. It is also called the “good fat”.

Perivascular Adipose Tissue: This is the fat present around blood vessels. It was long thought to have only a supporting role, but is now understood to have a major role in health and disease. It secretes biologically active chemicals and is involved with blood vessel inflammation.

Bone Marrow Adipose Tissue: As the name implies, this is the fat in bone marrows. Not a lot is known about its function yet, but it is probably related to bone mass.

Ectopic Hepatic Lipids: This is the fatty liver (Non-Alcoholic fatty Liver Disease NAFLD) that develops due to consumption of excess carbohydrates-“diabetes of the liver”. It is related to insulin resistance and is a risk factor for diabetes, heart disease and many more diseases. Fatty liver (NAFLD) can progress to NASH (Non-Alcoholic Steatohepatitis), fibrosis, cirrhosis and liver cancer. NAFLD is like an epidemic worldwide.

Subcutaneous Adipose Tissue (SAT) and Visceral Adipose Tissue (VAT): The acronym VAT reminds me of Hindi movies of the seventies where the villain usually drank VAT 69 , the whisky ! Excess VAT, ie the body’s VAT ,is fat that accumulates among the internal organs. This is very distinct from the SAT , which is fat beneath the skin. Excess VAT is related to a whole host of cardiometabolic diseases. Increased belly fat is usually excess VAT. SAT probably has protective functions. The apple-shaped body versus the pear-shaped body!

Epicardial Adipose Tissue: This is the fat present between 2 layers of the heart. I will not discuss all the different types of cardiac fat here, except to mention that excess epicardial fat is associated with many diseases like coronary artery disease (CAD),which is atherosclerotic thickening of the blood vessels supplying the heart, and insulin resistance.

Amongst all the different types of adipose tissue the ones most relevant to health (as far as knowledge goes today) are brown fat,SAT, VAT, liver fat and fat in the heart.

HOW DO YOU KNOW IF YOU HAVE EXCESS FAT IN THESE COMPARTMENTS?

Waist measurement and Waist-Hip Ratio:

As many of you know your BMI is not the best measure of health. This is particularly so for South Asians.This is because many of you are TOFI–Thin-Outside-Fat-Inside or “Skinny Fat”. This means that at a given body weight , you may have a higher body fat percentage than is healthy for you.

 

TOFI–THIN-OUTSIDE-FAT-OUTSIDE

 

KNOW YOUR NUMBERS:
Waist Circumference:

Men: Waist circumference 85-90 cm (34”) or more is unhealthy.

Women: Waist circumference 80 cm (31.5”) or more is unhealthy.

The easiest way to measure this is by measuring your waist size with a tape measure at the level of the belly button.

Waist to Hip Ratio:

Divide your waist circumference by your hip circumference.

Hip circumference: Measure the circumference of your hips at the widest point of your buttocks.

Healthy Waist/Hip ratio : Men 0.90  , Women 0.80.

Blood Tests: (Basic)
  1. Fasting Blood Sugar
  2. Post Meal Blood sugar
  3. Fasting Insulin.
  4. Triglycerides
  5. Hs-CRP
  6. AST,ALT (SGOT,SGPT)
  7. GGT
Weighing Scales :

Weighing scales that show your body fat and lean mass percentage are acceptable measures of health.

Imaging:

Ultrasonography of whole abdomen can detect fatty liver.

Echocardiography: To detect heart function and fat.Currently, there is no consensus on the ‘gold standard’ for quantification of cardiac fat.

MRI: Costs more.

PET, DXA,CT scans: Radiation exposure. I don’t usually recommend these tests only to quantify body fat

SUMMARY

  • If you have belly fat, it puts you at a high risk for diseases like diabetes, heart disease, dementia, cancer.
  • Belly fat relates to insulin resistance.
  • You do not get fat by eating good quality fat. It is very likely that you eat more carbohydrate than is good for you.
  • A recent study called the PURE study in a prestigious journal The Lancet,showed that eating excess carbohydrate , not saturated fat puts you at higher risk of dying.
  • Dietary carbohydrate gets stored as body fat.
  • Know your basic blood numbers. (You will need someone knowledgeable in this field to interpret the numbers. Please remember that “in normal range” is not necessarily optimal).
  • If you are insulin resistant it is very likely that you have fatty liver and higher cardiac fat.
  • Total body weight is not the best measure of health.—Remember TOFI! This means that your skinny friend may not necessarily be healthy!

REFERENCES:

Porter, Stacy A., et al. "Abdominal subcutaneous adipose tissue: a protective fat depot?." Diabetes care 32.6 (2009): 1068-1075.

Dehghan, Mahshid, et al. "Associations of fats and carbohydrate intake with cardiovascular disease and mortality in 18 countries from five continents (PURE): a prospective cohort study." The Lancet (2017).

 

 

 

 

 

 

A DIFFERENT DIABETES: LATENT AUTOIMMUNE DIABETES OF THE ADULT (LADA)

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WHAT IS LADA?

Latent Autoimmune Diabetes of the Adult (LADA) is a type of autoimmune diabetes which shares common features between type 1 and type 2 diabetes.It is also called Type 1.5 diabetes or slowly progressive autoimmune diabetes.The 3 common criteria for diagnosis of LADA are:
  • Adult onset:the age at diagnosis ranges from 15 to 30 years.However, nowadays Type 2 diabetes is being diagnosed in increasingly younger people.The youngest person to be diagnosed with type 2 diabetes is a three year old girl in Texas, USA.
  • Antibody positivity: Diabetes Associated Antibodies (DAA) are usually present in people with LADA.However this may not be quite so clear-cut, given that different laboratories may have different cut-off values.These DAA include antibodies to glutamic acid decarboxylase 65 (GAD 65), insulinoma-associated antigen, islet cell & zinc transporter 8. The commonest is GAD 65 antibody.Antibody levels may fluctuate and the type of positive antibody may change over a period of time.Even a transient increase in autoantibody indicates autoimmunity.
  • Insulin treatment: Arbitrary definition of LADA include a period without insulin treatment of at least six months, but the need to use insulin is usually at the discretion of the physician.

WHY DO YOU NEED TO KNOW IF YOU HAVE LADA?

  • Patients with LADA generally have worse HbA1c levels (measure of 3 month’s average blood sugar) than type 2 diabetes patients.
  • Often they are misdiagnosed as type 2 diabetes.Incorrect treatment will lead to higher loss of insulin producing beta cells of pancreas.
  • Studies have shown that patients with LADA need insulin treatment earlier than those with type 2 diabetes and therefore may need closer monitoring.
  • Patients with LADA have lower levels of C-Peptide. (Connecting peptide is a marker of insulin production by your body). C-Peptide levels influence treatment.
  • The sulphonylurea group of drugs like chlorpropamide,glyburide,glipizide etc which work by stimulating the pancreas to release more insulin, are not the right choice of drugs for people with LADA.
  • Despite greater use of insulin, patients with LADA have worse blood sugar control. Therefore there is something more that needs to be done.
  • When any one autoimmune condition is present, the chances of developing others are high. People with LADA have a higher incidence of thyroid autoimmunity. Hence it is important to screen for other diseases as well.

WHAT IS DIFFERENT ABOUT A FUNCTIONAL AND METABOLIC MEDICINE APPROACH?

In addition to testing for DAA we would look at the following:

  • Gut Health.
  • Gut dysbiosis
  • Intestinal Permeability Dysfunction (Leaky Gut)
  • Vitamin D3 levels
  • Chronic Inflammation
  • Sleep
  • Nutrient Depletion
  • Stress Response
  • Movement/Exercise
  • Test for other autoimmune conditions, particularly thyroid autoantibodies.
  • Risk for heart disease and stroke
  • Check for heart failure.

Should everybody be screened for LADA?

That will depend on your goals.I practice patient-participatory medicine. My duty as a physician is to provide you with correct information and help  you make the best decision for yourself.

You MAY BE INTERESTED IN READING:

Do you have autoimmune diabetes

Predictive Autoantibodies

Vitamin D and Autoimmunity

Ebook on Autoimmunity

REFERENCES
Gambelunghe, Giovanni, et al. "Increased risk for endocrine autoimmunity in Italian type 2 diabetic patients with GAD65 autoantibodies." Clinical endocrinology 52.5 (2000): 565-573.
Priyanka P. Brahmkshatriya, Anita A. Mehta, Banshi D. Saboo, and Ramesh K. Goyal, “Characteristics and Prevalence of Latent Autoimmune Diabetes in Adults (LADA),” ISRN Pharmacology, vol. 2012, Article ID 580202, 8 pages, 2012. doi:10.5402/2012/580202

CIRCADIAN DISRUPTION: ARE YOUR MEALTIMES AFFECTING YOUR METABOLISM?

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Your body has an internal biological clock which decides when you sleep, eat, wake up, secrete hormones, process food and do many more functions.

The term circadian comes from the Latin word circa, meaning “approximately”, and diēm, meaning “day”. This daily rhythm is related to Earth’s rotation around its own axis which exposes all living beings to a 24-hour light-dark and temperature cycle.

Chronobiology is the science or study of the effect of time, especially rhythms, on living systems (including humans).

In the last several years many scientific studies have shown that the disruption of the circadian rhythm is related to a higher incidence of many conditions like Type 2 Diabetes, heart disease, inflammation, mood disorders, some cancers and obesity. In fact, rotating night shift–work has been called a probable carcinogen (cancer causing) by the World Health Organization. Night shift work and light at night(LAN) have been associated with a higher risk for breast cancer in women.

BASICS OF CIRCADIAN RHYTHM

Your body’s circadian rhythm is controlled by a circadian clock. The master clock is in the brain (Suprachiasmatic Nucleus SCN) and this controls all the other clocks in the other organs (peripheral clocks). Every cell in your body has this intrinsic clock and there are genes involved in the clock mechanisms. In fact, the clock is present even in cells in a petri dish in the lab!

Clocks

Fig: Central clock in the Suprachiasmatic Nucleus in the brain and peripheral clocks in different organs.Zeitgebers: Light on retina and food intake.

Although circadian rhythms are built-in and self-sustained, external cues can modulate circadian rhythms.

What are the external cues (zeitgebers) modulating your circadian rhythm?

  • Light falling on your eyes.

(Nerd Alert: Retinal melanopsin influences this. Loss of melanopsin retinal cells may be related to dysregulation of circadian rhythm in  Alzheimer’s Disease )

  • Intake of food
  • External temperature.

CHRONONUTRITION:

Chrononutrition refers to food intake in coordination with your body’s daily rhythm. This concept implies that in addition to the type of food you consume, the time of ingestion is also critical for your health and well-being.

STUDY USING A SMARTPHONE APP:

In an interesting study reported in the journal Cell Metabolism (2015), Dr. Satchidananda Panda and Shubhroz Gill used a smartphone app to track eating patterns in healthy men and women who were living regular lives (not in a lab). The smartphone app was used to take pictures of everything that they ate or drank. This was done for 3 weeks.

WHAT DID THEY FIND:

  • Most food (53.6%) was consumed after 6 PM, with less than 25% of caloric intake occurring before noon.

(My comments: Why is this important? This is related to your insulin secretion and insulin sensitivity. Lower Insulin sensitivity (IS) means higher body fat percentage and higher risk for Type 2 Diabetes and a whole host of diseases.) IS tends to be higher at breakfast than at lunch or dinner. So if most of your food intake occurs at a time of the day when you are less insulin sensitive, what can happen? You can become metabolically dysregulated and insulin resistant. This is a big problem in Asian Indians because diabetes and heart disease strikes them at least a decade before it does in the Western population. My dictum is “all Asian Indians are either pre-diabetic or diabetic until proven otherwise”)

  • Only 25% of the meals occurred after >6 hours 41 min of fasting.
  • About 90 % of people in the study ate for 14 hours 45 minutes in a day.
  • In another part of the study, 8 people who ate for more than 14 hours in a day, were asked to reduce their eating duration to 10-12 hours and to follow the same pattern during week days and weekends.

What did they find?

  • In 16 weeks of study duration the participants lost 3.27 kilograms of body weight!
  • These 8 people on the time restricted eating (TRE) program reported better sleep, better energy levels and less hunger at bedtime.
  • These people voluntarily agreed to stay on this eating pattern and they maintained their weight loss and sleep improvement and higher energy levels 1 year after they started on TRE. All this improvement from just restricting your eating from >14 hours to 10-12 hours! This is major!

Though the study did not mention testing for inflammatory markers or blood sugar and insulin, I am sure if they had measured, they would have found improvements in these biomarkers as well.

Weight loss is not a simple problem of calorie-in-calorie-out(CICO). I prefer to say fat loss because your weight includes your muscles and bones too. You don’t want to lose muscle! (More on this later).

ACTION STEPS:

  • Download and use the app (REFERENCES SECTION) and track for yourself. You will get great insight.
  • Implement Time Restricted Eating and see the difference in your health.
  • Eat an early dinner: This is a big challenge in many Asian Indian homes but try moving your dinner time by half hour every week until you have your dinner around 6:30-7 PM everyday.May be difficult to change dinner time from 9:30 PM to 6:30 PM in one day.
  • I know some of you do not reach home in time to have an early dinner. Maybe you can carry a second box of home cooked food to eat in the office or on the commute.
  • If you reach home by 7 PM, have your dinner at that time  instead of eating snacks then and save yourself from a late dinner just before you go to bed.

(Watch for post on “metabolic/social” jetlag ,later)

REFERENCES:

myCC

Picture:App myCircadianClock.

Android:https://play.google.com/store/apps/details?id=com.salk.mycircadianclock&hl=en

iTunes:https://itunes.apple.com/ca/app/mycircadianclock/id982118665?mt=8

La Morgia, Chiara, et al. “Melanopsin-expressing retinal ganglion cells: implications for human diseases.” Vision research 51.2 (2011): 296-302. La Morgia, Chiara et al.

Melanopsin Retinal Ganglion Cell Loss in Alzheimer Disease.” Annals of Neurology 79.1 (2016): 90–109. PMC. Web. 18 Aug. 2016.

Gill, Shubhroz, and Satchidananda Panda. “A smartphone app reveals erratic diurnal eating patterns in humans that can be modulated for health benefits.”Cell metabolism 22.5 (2015): 789-798.

Time for Food: The Intimate Interplay between Nutrition, Metabolism, and the Circadian Clock Asher, Gad et al. Cell, Volume 161, Issue 1, 84 – 92

Saad, Ahmed, et al. “Diurnal pattern to insulin secretion and insulin action in healthy individuals.” Diabetes 61.11 (2012): 2691-2700.