Insulin: The Underrated Key to Metabolism, Performance, and Longevity

When we talk about metabolism, most people immediately think of calories or cortisol. But one

of the most powerful and underrated players in this entire system is insulin. This hormone

doesn’t just regulate your blood sugar—it dictates how your body responds to food, recovers

from training, stores fat, builds muscle, and ultimately how resilient and energized you feel day

to day.

Insulin is released by the pancreas when blood sugar rises, typically after eating—especially

meals that contain carbohydrates. Its job is to move that glucose out of your bloodstream and

into your cells, where it can be used for fuel or stored for later use. Think of it like a messenger:

it’s telling your body,

“Hey, energy just came in—here’s what to do with it.”

But insulin isn’t good or bad. It’s a signaling hormone, and its impact depends entirely on your

internal environment. We want a healthy insulin response after meals. We need it to be

functioning properly. Issues arise when insulin is chronically elevated—usually from excess food

intake, chronic stress, or a mismatch between energy intake and output—which leads to insulin

resistance over time.

Metabolism Is Always Adapting: The Fed vs. Fasted State

Your metabolism isn’t fixed. It shifts constantly between two states: the fed state and the fasted

state. Each has its own purpose and set of dominant hormones, and healthy metabolism means

your body can toggle between these two states efficiently.

The fed state is an anabolic state—it’s all about growth, repair, and replenishment. This state

kicks in right after you eat. Nutrients like carbohydrates, proteins, and fats are converted into

usable energy or stored for later, and insulin is the main hormone leading the charge. The fed

state is marked by a high insulin-to-glucagon ratio. It’s when your body builds lean tissue,

restores glycogen, supports hormone production, and prepares for future energy demands.

But if you're in a fed state too often—especially with a surplus of calories and low

movement—your cells may stop responding efficiently to insulin. This can spiral into insulin

resistance, weight gain, energy crashes, cravings, and inflammatory issues. Over time, it may

evolve into metabolic syndrome or conditions like PCOS, especially when layered with stress or

poor sleep.

The fasted state is a catabolic state. It kicks in when nutrients aren’t readily available in the

bloodstream. The body first uses stored glycogen and eventually shifts toward burning fat and

producing ketones. This state is marked by a low insulin-to-high glucagon ratio, and otherkey hormones like cortisol and catecholamines (epinephrine and norepinephrine) step in to

liberate energy from stored fuel.

The fasted state has a ton of benefits—it increases fat oxidation, supports metabolic flexibility,

and helps regulate blood sugar. But when pushed too far—either through chronic undereating,

overtraining, or stress—it can backfire. The stress response (HPA axis) stays activated, while

systems like the thyroid (HPT axis) and reproductive hormones (HPG axis) downregulate. That’s

when people start feeling cold all the time, experience poor sleep, digestion slows down, libido

drops, and energy tanks. It's not just a "fuel problem"

—it’s your body adapting to survive.

Lifestyle and Nutrition Interventions for Insulin Sensitivity

Rather than trying to keep insulin suppressed all the time, the real goal is insulin

sensitivity—teaching the body to respond efficiently to insulin when it’s needed, and return to

baseline smoothly. This creates metabolic flexibility, where the body can handle both fuel

abundance and fuel scarcity with ease.

So how do we become more insulin sensitive?

It starts with movement.

● Strength training builds muscle, which is your primary glucose sink—meaning more

muscle allows for better glucose uptake and storage.

● Cardio helps too, but how much and what kind depends on your physiology and goals.

For some, walking and Zone 2 cardio are enough. For others, more intensity may be

layered in strategically.

● Daily movement like walking after meals, taking the stairs, or light mobility work all

support better blood sugar management.

Next up: stress management. Chronic stress keeps cortisol elevated, which interferes with

insulin function and energy regulation. Tools like breathwork, meditation, journaling, getting out

in nature, or even just scheduling things you enjoy (fun counts as a health strategy!) can help

shift your nervous system out of “survival mode” and support metabolic recovery.

Sleep and circadian hygiene are non-negotiable. Aim for 7–8 hours of quality sleep per night.

Support your circadian rhythm by getting morning sunlight, eating more of your calories during

daylight hours, and cutting off food intake 3–6 hours before bed (a strategy called early

time-restricted feeding). When sleep is off—even for one night—insulin resistance can spike by

20–30%.

Then there’s your dietary approach.

• Keep protein high—this supports muscle maintenance, hormone production, and stable

blood sugar.

• Carbohydrate intake should be tailored to your activity level. If someone is more

sedentary or dealing with insulin resistance, a lower-carb approach may be helpful. But if

you’re lifting weights, doing cardio, or recovering from training, your body needs more

carbs—and when used strategically, they’ll support better insulin sensitivity, not worse.

• Pay attention to biofeedback: if you’re crashing midday, getting brain fog, or feel wiped

after workouts, it could be a sign that carbs need to be adjusted.

• Add fiber-rich vegetables to every meal. They help blunt glucose spikes, support

digestion, and create more satiety without driving up calorie load.

This isn't about one perfect meal or a strict set of rules—it’s about giving your body the right

information, consistently. Insulin is listening. The question is: are you sending the right signals?

The Bottom Line

Insulin doesn’t just manage sugar—it’s a key messenger for your metabolism. When insulin and

glucagon are balanced, your body is resilient, responsive, and adaptable. You recover better,

perform stronger, and avoid the metabolic extremes that lead to burnout or dysfunction.

This isn’t about avoiding food or chasing low insulin levels. It’s about cultivating metabolic

flexibility—the ability to shift between fuel states smoothly and efficiently. And that starts with

lifestyle strategies that work with your biology, not against it.

If cortisol is your alarm system, insulin is your thermostat. And when both are regulated, your

whole body runs better.