Zane Griggs

Zane Griggs For high performers who feel off
Data-driven metabolic correction
Stop guessing. Get clarity.
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www.zanegriggs.com

Following my passion for health and fitness, I became a certified personal trainer in 1998.... and that's when the education really began. Working with many, different people, I found that the textbook nutritional guidelines were really not effective for many of my clients to achieve a healthy weight. This was especially true if the person were obese or had another metabolic issue. As I began looking for alternative sources of information I found that the people who much of the fitness and nutrition industry considered to be "questionable", were actually getting results with their methods and had biological explanations for it. I've had the great opportunity to work with one of the popular weight loss shows for two seasons, one for the entire season and the other for the last three months, to help two participants lose approximately half of their body weight. These were not only incredible learning experiences but also very inspiring. I was actually both frustrated and inspired. Frustrated by the false messages being sold to the public by the government and health authorities, as well as the food industry profiting from and perpetuating the misinformation, while we, as a nation, continue to get fatter and sicker. Inspired to explain the truth about our food and how our bodies work to whomever will listen in a clear and approachable way.

High blood sugar is not the whole story.We tend to treat elevated glucose as if the glucose itself explains everything. ...
09/18/2026

High blood sugar is not the whole story.

We tend to treat elevated glucose as if the glucose itself explains everything. Blood sugar goes up, so we focus entirely on getting the number back down.

But glucose is fuel in transit. The more important question is: why isn’t the body handling and using that fuel efficiently?

To understand that, you have to look at cellular energy production.

Your cells use glucose and other fuels to produce ATP. That ATP powers virtually everything—muscle contraction, cellular repair, membrane function, ion balance, neurological function and the basic maintenance required to keep tissues healthy.

When glucose oxidation and mitochondrial energy production aren’t working efficiently, the body doesn’t simply shut down. It compensates.

Stress hormones such as cortisol and adrenaline can rise. Glucagon can increase liver glucose output. Fatty acids can be mobilized for additional fuel. These are normal survival mechanisms, but chronically relying on them can create a metabolic environment where glucose regulation becomes increasingly difficult.

This is why I don’t look at elevated blood sugar as an isolated problem.
I want to know what’s happening with insulin. Liver function. Muscle mass. Sleep. Circadian rhythm. Inflammation. Nutrient status. Stress hormones. Activity levels. Fuel availability. And, ultimately, how effectively the body is producing and using energy.

Because simply forcing glucose lower doesn’t necessarily tell you why it became elevated in the first place.

And chronically elevated glucose still matters. It can contribute to oxidative stress, glycation, vascular injury and diabetic complications. The point isn’t that glucose is harmless.

The point is that the number is giving you information about a much larger system.

The goal should be more than making one biomarker look better.

Improve metabolic function. Improve insulin sensitivity. Build muscle. Support mitochondrial energy production. Sleep. Recover. Fuel appropriately. Reduce unnecessary metabolic stress.

Find out what’s feeding the fire.

09/16/2026

The common explanation goes like this: Carbs raise insulin → insulin stops fat burning → repeated insulin spikes eventually cause insulin resistance.

That explanation for insulin resistance is obsolete and not supported by the last 20 years of research, 80 years of high carb, low fat dietary interventions and several indigenous populations that consume a diet of 60-80% carbohydrates with excellent metabolic health.

As I explain in the video, insulin can strongly suppress the release of stored fat after a meal without completely shutting down fat oxidation.

Those are two different processes.

Your body is supposed to change its fuel selection after you eat. When glucose becomes available, carbohydrate oxidation rises, fat mobilization falls, and your metabolism shifts toward using more of the incoming fuel.

That’s normal metabolic flexibility—not metabolic dysfunction.

So what actually contributes to insulin resistance?

One important mechanism researchers have identified is the accumulation of lipid intermediates such as diacylglycerols (DAGs) and ceramides inside insulin-sensitive tissues.

These can interfere with insulin signaling in the liver, fat cells and muscle. Insulin may be present, but the cells become less responsive to its message.

Now muscle has more difficulty taking up glucose, the liver doesn’t suppress glucose production appropriately, and the pancreas may compensate by producing even more insulin.

In other words, chronically high insulin can be a response to insulin resistance—not proof that insulin caused it.

That changes the question entirely.

Instead of asking, “How do I keep insulin from rising after a meal?”

Ask, “How do I make my body more insulin sensitive?”

Build muscle. Move every day. Reduce ectopic fat (DAG’s & ceramides). Improve sleep and recovery. Eat minimally processed foods. And stop assuming whole-food carbohydrates like fruit, potatoes and rice are creating the problem simply because they produce a normal insulin response.

The goal isn’t zero insulin elevations. The goal is a metabolically healthy body that responds appropriately when insulin shows up.

Research: PMID 11872660, 23054552, 2

Ketones are an incredible survival adaptation. That doesn’t mean they’re the fuel your brain was designed to use exclusi...
09/11/2026

Ketones are an incredible survival adaptation. That doesn’t mean they’re the fuel your brain was designed to use exclusively.

Under normal mixed-diet conditions, glucose supplies 90-100% of the brain’s energy. When carbohydrate availability falls substantially—as occurs during fasting or a ketogenic diet—the liver begins producing ketone bodies from fatty acids.

The brain then adapts.

As ketosis continues, ketones can provide a substantial portion of its energy requirements, reducing the amount of glucose that must be supplied by 50-70%.

That’s metabolically impressive. But it doesn’t mean glucose suddenly becomes unnecessary.

Even during prolonged ketosis, glucose-dependent metabolism continues. The body maintains blood glucose through gluconeogenesis because certain tissues and metabolic pathways still require it, i.e. red blood cells, neurons, te**es, replicating cells, the kidney medulla and certain tissues in our eyes.

Long term, further adaptations like reduced thyroid function, elevated glucagon levels and adaptive insulin resistance to preserve glucose for the brain and other tissues that require glucose which can lead to elevated fasting glucose levels.

We can use both.

Your metabolism is designed to respond to changes in fuel availability. After eating carbohydrates, glucose oxidation rises and ketone production falls. During fasting or carbohydrate restriction, fatty-acid oxidation and ketone production rise.
That’s metabolic flexibility.

Our bodies are always using fat for energy in either case. The difference is to what degree.

The more useful question is whether your body can appropriately switch between glucose and fat, produce energy efficiently, maintain stable blood sugar and respond normally to the food you eat.

Many people who have been on an extended ketogenic diet have “adapted” to the point that oxidizing glucose becomes a problem.

Ketones are useful when our preferred energy sources are scarce.

Glucose is the preferred fuel to maintain homeostasis and hormone balance.

Optimal health is not achieved by remaining in a survival mechanism.

09/10/2026

What if carbs aren’t what’s keeping women from losing weight after menopause?

Because in this study, postmenopausal women ate a diet with no caloric restrictions, dramatically increased the proportion of carbohydrate in their diet — and lost an average of 13 pounds.

No calorie target.
No prescribed calorie deficit.
No low-carb diet.

Researchers instructed 54 postmenopausal women to eat as much as they wanted for eight months, with one primary dietary intervention: keep fat below 15% of calories.

Their average fat intake fell from roughly 33% of calories to 11%.

And they lost an average of 6 kg — about 13 pounds.

Here’s the part that gets overlooked:
Fiber intake increased from 16 to 23 grams per day.

When dietary fat falls that dramatically while fiber intake rises, the diet necessarily shifts toward more carbohydrate-rich foods.

Yet these women still lost weight.

That matters because women are often told that after menopause, carbohydrates become the problem. Insulin becomes the problem. And the solution is to keep removing carbs and eating less.

But this study gives us a very different picture.

It doesn’t prove that everyone should eat an 11% fat diet. And it certainly doesn’t mean dietary fat is bad.

What it demonstrates is that carbohydrates are completely compatible with meaningful fat loss after menopause.

The metabolic context matters.

Food selection matters. Dietary fat matters. Fiber matters. Activity and muscle mass matter.

Reducing the entire conversation to “carbs raise insulin, so carbs make you fat” misses the bigger picture.

For some women who have spent years cutting carbohydrates while increasing dietary fat, the answer may actually look very different: More carbohydrates. Less dietary fat. More food volume. And a metabolism that has enough fuel to function.

Stop fearing one macronutrient and start looking at the entire metabolic picture.

Study: Mueller-Cunningham et al. | PMID: 14647085

09/07/2026

Your vision is trainable.

One of my biggest takeaways from my conversation with Dr. Bryce Appelbaum was how much we can actually do to improve the way our eyes and brain work together.

I’ve been working through his vision exercises myself, and I noticed a difference after the first round of eye stretches. Now I find myself doing them first thing in the morning—even when I’m not going through the full program.

Just like training your body, the right exercises, done consistently, can make a difference.

And in a world where we spend hours staring at screens, training our vision may be more important than ever.
Great conversation with Dr. Bryce Appelbaum. Thanks for coming on Healthy AF and sharing your work with us, Dr. Bryce Appelbaum

🎧 Watch the full episode of Healthy AF to learn more about vision training, screen time, performance, and keeping your eyes and brain working together as you age.

09/03/2026

Insulin resistance isn’t caused by eating carbs and “spiking insulin” over and over.

That explanation has dominated the internet for years: carbs raise insulin, too much insulin eventually makes your cells resistant, so the solution is to avoid carbohydrates.

But that leaves out a major part of the physiology.

One mechanism strongly implicated in insulin resistance is the accumulation of lipid intermediates called diacylglycerols (DAGs) and ceramides inside tissues like the liver, fat cells and skeletal muscle.

Normally after you eat, insulin sends a message: muscle should take up glucose, the liver should reduce glucose production, and fat tissue should slow the release of fatty acids.

With insulin resistance, insulin can be there and the receptor can receive it, but the signal becomes impaired.

In skeletal muscle, DAG accumulation can activate PKC pathways that interfere with insulin signaling and reduce glucose uptake. Ectopic fat in the liver can impair insulin’s ability to suppress glucose production and release into the bloodstream.

So now you have an interesting situation:

Insulin is HIGH, but the message isn’t being properly received.

Muscle struggles to take up glucose efficiently. The liver continues releasing glucose when it shouldn’t. Fat metabolism becomes dysregulated. The pancreas responds by producing even more insulin to compensate.

That’s insulin resistance.

And it changes how we should think about fixing it.

The goal isn’t simply to spend your life avoiding foods that produce a normal insulin response.

It’s to address the metabolic environment creating the resistance in the first place.

Reduce excess calories and dietary fat when appropriate. Build muscle. Move every day. Improve sleep. Choose minimally processed foods. And don’t fear whole-food carbohydrates like fruit, potatoes and rice.

The goal isn’t to avoid insulin. It’s to restore insulin sensitivity.

That’s a very different strategy.

Research: PMID 11872660, 23054552, 28591572.

09/03/2026

If nearly 60% of the American diet comes from ultra-processed foods, what does that mean for long-term health?

This conversation explores how highly processed foods, added sugars, poor nutrient density, and convenience-driven eating can shape metabolic health. The solution doesn’t have to be complicated: prioritize whole foods, quality protein, fiber, better ingredients, and everyday choices that make healthy eating sustainable.

Somewhere along the way, getting healthy became incredibly complicated.People will spend thousands of dollars trying to ...
09/01/2026

Somewhere along the way, getting healthy became incredibly complicated.

People will spend thousands of dollars trying to optimize themselves while ignoring the basic physiology underneath all of it.

They’ll track sleep without sleeping enough. Track recovery without recovering. Fast while training hard. Cut carbohydrates while complaining about performance. Take a cabinet full of supplements without knowing whether they actually need them. And they’ll spend years manipulating their diet without ever looking at the metabolic markers that could tell them what is actually happening.

I’m not against technology, supplements or advanced strategies. I use plenty of them.

But optimization should come after the foundation, not instead of it.

Eat enough food. Build muscle. Move every day. Sleep. Recover. Manage metabolic stress. Fuel your training. And get objective data instead of assuming that because you’re doing all the things the health internet told you to do, they’re actually working for your physiology.

Especially after 40, I care a lot less about how impressive your health routine looks and a lot more about what the results say.

How do you feel? How do you perform? How are you recovering? Are you maintaining muscle? What is happening with glucose, insulin, thyroid, lipids and the other markers that give us a picture of metabolic health?

Your body doesn’t care how good your health routine looks on Instagram.

It responds to the environment you’re actually creating.

Comment GUIDE and I’ll send you my free Metabolic Stress Marker Guide.
Comment LABS if you’re done guessing and want to order your labs and build a plan around your actual results.

08/31/2026

High blood sugar is not the whole story.

We tend to look at an elevated glucose or A1C reading and immediately make glucose the problem. The assumption becomes that there is simply too much sugar in the blood, so the solution must be to eat less sugar, cut carbohydrates, or find another way to force that number down.

But glucose regulation is downstream of a much larger metabolic system.

One important part of that system is mitochondrial function. Your mitochondria convert fuel into ATP, the usable energy your cells require to do essentially everything. ATP supports cellular repair, membrane integrity, ion balance, muscle contraction, hormone production, neurological function and countless other processes happening every second.

When energy metabolism becomes impaired, glucose regulation can become impaired with it. Cells may become less effective at handling and oxidizing fuel, insulin sensitivity can decline, and blood glucose can begin to rise.

At the same time, inadequate cellular energy can affect the body’s ability to maintain and repair tissue. This is one reason I don’t think it makes sense to look at elevated blood sugar in isolation and assume the glucose itself tells us the entire story.

The question shouldn’t only be, “How do we get this number down?”

It should also be, “Why is the body struggling to process and use energy efficiently in the first place?”

That requires looking beyond a single glucose reading. Insulin, triglycerides, thyroid markers, inflammation, stress hormones, sleep, recovery, nutrition and other metabolic markers can help us understand the environment that glucose is responding to.

The goal is not simply a better number on a lab report. The goal is better metabolic function: improving the body’s ability to produce ATP, use fuel efficiently, respond appropriately to insulin and maintain healthy cellular function.

When you understand the physiology underneath the number, you can stop guessing about what your body actually needs.

Comment GUIDE and I’ll send you the metabolic markers I look at, or comment LABS if you want to order your labs and get a plan based on your results.

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