A fasting glucose of 98 mg/dL is not a problem. A fasting glucose of 98 mg/dL every year for eight years, drifting from 88, is the problem. Most lab reports will flag neither. The interesting medicine lives in the trendline, and the trendline is where most members are not looking.
Metabolic dysfunction is the slowest moving of the major longevity threats. Hypertension declares itself. Lipids declare themselves. Metabolic drift whispers. The lab-reference upper bound for fasting glucose in the United States is 99 mg/dL, and the upper bound for HbA1c is 5.6 percent. A member can sit at 98 and 5.5, respectively, for a decade, be told they are “normal” eleven times in a row, and arrive at their fifties already holding the loaded question.
The optimal range, to our medical team, is tighter than the lab range. This piece is about why, and about what the discipline of holding the tighter range actually looks like.
What the numbers measure, precisely
Fasting glucose is a snapshot — the concentration of glucose in the blood after an overnight fast, reflecting the balance between hepatic glucose output and peripheral uptake. It moves around for reasons that have little to do with health: the dawn phenomenon, a late-night snack, a badly slept night before the draw. One reading tells you almost nothing. A sequence of readings tells you something.
HbA1c is the opposite kind of measurement — a non-enzymatic glycation of hemoglobin that integrates circulating glucose over the approximately 90-day lifespan of the red blood cell. It is quieter, slower, harder to game, and considerably more informative. It is also not perfect. Anemia, variant hemoglobins, recent transfusions, and iron-deficiency states can all move it without moving the underlying physiology. For members with those conditions, glycated albumin or fructosamine are useful secondary reads.
Together, the two numbers cover the snapshot and the average, and triangulating with post-prandial excursions — either from a continuous glucose monitor or from scheduled post-meal draws — gives the full picture. Most members have the first two; fewer have the third.
Why the lab range is too wide
The statistical answer is that reference ranges are built from population distributions. The upper bound is typically the 95th or 97.5th percentile of a reference sample. That is reasonable for flagging disease. It is unreasonable for flagging optimization, because a sizable fraction of the population in the reference sample is already metabolically unhealthy — the samples drawn at the lab include people on their way to the diagnosis, not only people distant from it.
The clinical consequence is that a value at the 95th percentile of the reference range is not healthy. It is normal in the statistical sense, and drifting in the clinical sense. Our team treats optimal fasting glucose as 70 to 90 mg/dL and optimal HbA1c as below 5.3 percent, which tracks the metabolic literature on all-cause mortality curves more faithfully than the lab-flagged ranges do. The Diabetes Care 2021 analysis by Selvin and colleagues remains the cleanest read on where the mortality inflection actually lives.
The drift pattern we watch for
Annual labs are more valuable when plotted than when read individually. A member whose fasting glucose has moved from 86 to 89 to 92 to 96 over four years is not “still normal.” They are losing the argument with their insulin sensitivity, one annual draw at a time. By the time the number crosses 100, the underlying physiology has been sliding for half a decade.
HbA1c tracks it more gently. A movement from 5.1 to 5.3 in a year reads like noise. A movement from 5.1 to 5.3 to 5.5 over three years is a signal, and it is one worth intervening on. The intervention at 5.5 is dietary, mechanical, and cheap. The intervention at 6.4 is pharmaceutical, durable, and expensive in ways that compound.
What actually moves the numbers
The levers, in descending order of effect size in our practice:
- Post-meal movement. A 10-to-15-minute walk within an hour of the largest meal of the day moves post-prandial glucose excursions meaningfully in every CGM-equipped member we have measured. Bellini and colleagues published a 2022 meta-analysis putting the reduction at around 17 percent. No other cheap intervention comes close.
- Resistance training twice a week, minimum. Skeletal muscle is the single largest glucose disposal tissue in the body. Building it and using it under load is not primarily a physique intervention. It is a metabolic one.
- Sleep duration and timing. A single night of restricted sleep produces a transient state that looks a great deal like mild insulin resistance. Chronic short sleep produces the durable version. Members who protect a seven-to-nine-hour window are working on HbA1c whether they know it or not.
- Carbohydrate quality and timing. Not low-carb. Right-timed carb. Around training, post-training, and in the company of fiber and protein, most carbohydrates are fine. Alone, late, and liquid, they are expensive.
- Ultra-processed food frequency. The Hall et al. intervention from the NIH Clinical Center — the carefully controlled two-week crossover — remains the cleanest demonstration of why this ranks where it does.
Where WEF’s services fit
Our members hit the same metabolic drift that the population does, and the services we run address it in specific ways. HBOT enhances mitochondrial function in ways that make peripheral glucose disposal more efficient. Infrared sauna, practiced consistently, lowers fasting insulin in the Finnish cohort work. The DexaFit body composition scan, run quarterly, captures visceral fat trend — the single most clinically meaningful fat depot — before the scale catches the drift. Physician-formulated IV therapy includes NAD+, which supports sirtuin-mediated metabolic signaling in the context of a broader plan.
None of these are solutions alone. They are accelerants on a practice. The practice is the tighter range, held quietly, for years.
The slow conversation
You are the kind of person who already checks labs. The next increment is not an additional panel. It is the line-graph view of the panels you already have, with your name on each dot, and the willingness to notice the slope.
Fasting glucose of 98 is not a problem. The eight years it took to get there is the problem. The twelve years ahead, starting tonight at dinner and on the walk afterward, are the conversation.
— Published in The Bioneer, Journal. Reviewed by Dr. Swet Chaudhari, MD, Double Board-Certified Medical Director of Wellness Elite Fitness. This piece is informational; it is not medical advice. Consult your physician before beginning any new protocol.