Everything You Need to Know about Insulin and Fat Storage
Wednesday, August 22, 2018
LifeTime WeightLoss in Samantha McKinney, insulin and fat storage

When you hear the word insulin, what comes to mind? For most, it’s a neighbor, cousin or friend that is among the estimated 9.4% of Americans who have diabetes (9 out of 10 of which are Type 2, which is often more lifestyle driven).1,2 While, yes, the prevalence of diabetes is no doubt on the rise, not a single person is immune to the massive impact that insulin and blood sugar regulation have on body composition, longevity and overall health outcomes. Imbalances in blood sugar regulation are important to consider not only for efficient fat loss, but also due to the undeniable associations with cardiovascular disease risk, blood vessel damage, breast cancer, cognitive decline, increased levels of androgens (characteristically “male” hormones) in women and increased levels of estrogen in men, and overall risk of death.3-6


And - for a lot of us- we think we’re doing better than we actually are.

Let’s consider an angle that might feel more relatable. Does pizza always sound better to you than a chicken stir fry? After several hours without eating, do your co-workers or kids suddenly seem more irritating? Does ice cream have to go hand-in-hand with your favorite evening TV show? Do you toss and turn at night? Do you feel that, despite exercising, your belly fat just won’t budge? How is your energy after eating? Does it spike? Or does it plummet and make you wish you could take a power nap? (Surprisingly, the only thing you should feel after eating is “not hungry,” versus a change in energy level.)

If any of these apply to you, you’re not alone. Know that, while these are all surprisingly common pervasive, even they certainly are not normal. They might be a sign that you’re already on the long and insidious road to diabetes. Right now, it may be showing up as unwanted fat, fluctuating energy, and a disproportionate love of processed carbs. The good news? It’s possible to make a U-turn.


How it works

If you’re primarily interested in the “so what?” and less on the physiology, feel free to skip this section entirely and jump to the next one.

When we eat, our blood sugar rises. How much it rises depends on what we eat, how much, and in what balance. Carbohydrates such as bread, pasta, cereal, fruited yogurt, grains, brownies, chips and crackers will spike blood sugar much higher than foods that are predominantly dietary fat, protein, or fiber (think a leafy green salad topped with avocado and grass fed steak).

In response to rising blood sugar, the pancreas, a 6-inch long gland behind the stomach, releases insulin. As you might be aware, insulin lowers blood sugar, whether you have diabetes or not. (Think of that relative that manages diabetes by administering insulin around mealtime. For those of us without diabetes, our pancreas does all of the insulin administration for us). Do you ever wonder where the blood sugar goes? It does not just disappear.

If we’re in the middle of some rigorous activity, such as a triathlon, blood sugar may be put to use for energy to fuel activity. If this is not the case, it might get stored as glycogen (a storage form of carbs) in the liver or muscle. But, as is the case for most people, most of the time when not fasting or exercising intensely, glycogen stores are relatively full, so insulin converts blood sugar into body fat. And, as luck would have it, our fat stores are unlimited. (Go figure.) For this reason, insulin is referred to as an anabolic hormone, meaning it builds up instead of breaks down.

If blood sugar swings too low (which can happen if we go too long without eating, are in too much of a caloric deficit during exercise, or if the insulin release in response to eating is too high), the result can be irritability, sweating, headaches, shakiness, or nausea. The pancreas then releases insulin’s counter-hormone, glucagon, to break down stored carbohydrate and release sugar in the bloodstream.

Because excessively high blood sugar and excessively low blood sugar are both life-threatening, the body works really hard to keep blood sugar in balance. Ideally, blood sugar (and therefore insulin) oscillate in a gentle, relatively steady wave throughout the day, helping stabilize energy levels, mood and satiety. When things begin to go awry, both glucose and insulin end up with exaggerated peaks and valleys, creating excess stress, inflammation and accelerated aging.

Over time, cells start to ignore the constant bombardment of excess insulin, and the pancreas, in an ever-growing panic to keep blood sugar in check, is forced to work overtime to pump out more and more to try to get the cells to respond. This is referred to as insulin resistance. When the cells stop responding effectively to insulin, blood sugar stays high. Both insulin and blood sugar then evolve to chronically elevated states, until the pancreas eventually wears out, unable to keep up with excess insulin demands. Thus, Type 2 diabetes is born.

Looking under the hood: How do I know if I have an insulin issue?

We believe that health and disease are on a spectrum, and no one goes to bed healthy only to wake up the next day with a chronic disease like Type 2 diabetes. This entire process occurs over years, if not decades. The earlier it’s addressed, the better.

Subjective symptoms give us constant hints that something might be off and should be addressed. To boot, belly fat actually serves as one of the biggest risk factors of glucose imbalance. However, without regular, objective blood testing, it’s impossible to know your unique inside story with certainty, so testing is non-negotiable in strategically addressing long term health and success.7 That being said, it’s not as simple as checking blood sugar levels alone, as even the “normal” range of blood glucose on conventional tests may not be good for heart health.8 Plus, we’re often not told to start watching blood sugar until fasting levels are over 100 mg/dL. However, it’s been found that, even when fasting blood glucose is in-range, every point above 84 mg/dL can increase diabetes risk by a whopping 6%!9  It goes without saying that a “normal” fasting blood sugar level may not tell us much, and by the time it rises, it may be too late.10 

Luckily, other markers can serve as warning signs that it’s time to take more action. In particular, C-reactive protein (a marker of inflammation), ferritin (an iron storage marker that can also spike when something is wrong) and Hemoglobin A1C (a 3-month marker of blood sugar regulation that tests how much glucose is “stuck” on one of our blood proteins) can all serve as signs of insulin resistance.11 When testing these, remember that the reference range may be normal, but may not be optimal. Most laboratory reference ranges are determined by finding the average result and extending out two standard deviations to set the upper and lower limits, instead of determining what the range for true health really could be. If you’re on the upper end of the reference range on any of those three markers, be sure to discuss a plan with your doctor.

In addition, getting a better understanding of insulin levels (remember, it’s the main hormone that promotes fat storage) by testing C-peptide can be eye-opening.12 Take note, C-peptide is released in the same amounts and at the same times as insulin, but with a longer half-life. It may be a more stable and reliable measurement than direct insulin itself, and aiming for an upper limit goal of 2.5 ng/mL may be prudent, as suppression of insulin is associated with weight loss and a reduction in cravings.13 Together with regular fasting glucose measurements, these indicators can provide you the insight you need to put together a more targeted action plan with your health care team.

What to do

While the deleterious effects of blood sugar imbalances seem all doom and gloom, the amazing news is that we actually have a lot of control over how the body manages glucose and insulin. Here are my eight favorite strategies to help reclaim the balance:

There you have it-- everything you wanted to know about insulin and fat loss. As you can see, it’s a big topic that deserves the utmost attention when working toward your health and fitness goals. Without proper blood sugar and insulin regulation, attaining your optimal body composition, mental acuity, and quality of life is nearly impossible. Be sure to test your body’s functioning through assessment of both symptomology and blood work regularly and often, all while focusing on an unprocessed foods diet that is high in plants and quality protein and an exercise routine that includes regular resistance training. While insulin imbalances may be the root of trouble losing fat (and a long list of health maladies), we have more control over the outcome than many of us realize.

If you're looking for more support with your eating, simply enter your name and email below to get our full 67-page Eat Well, Live Well guide. We designed this guide to offer you the latest practical information, and easy-to-use strategies, to help you in your journey toward a healthier and more satisfying lifestyle. 



In health, Samantha McKinney — Life Time Lab Testing Program Manager  

This article is not intended for the treatment or prevention of disease, nor as a substitute for medical treatment, nor as an alternative to medical advice. Use of recommendations in this and other articles is at the choice and risk of the reader.


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