The Blood Tests Your Doctor Isn't Running (But Should Be)

You go in for your annual physical. Your doctor orders labs. A week later, a message lands in your patient portal: "Results normal. See you next year."

You feel reassured. Everything is fine.

Except it might not be.

The blood tests your doctor isn't running are often the ones that catch trouble years early. The standard panel your primary care physician orders typically includes 15 to 20 markers: a complete blood count (CBC), a basic or comprehensive metabolic panel, a standard lipid panel, maybe a TSH and an HbA1c.

Start with the one on that list you have already had. A standard lipid panel reports your LDL cholesterol, the amount of cholesterol riding inside the particles. It never counts the particles. ApoB counts them, and the count is what drives plaque.

These tests were designed to detect disease that has already arrived. They were not built to catch the metabolic and hormonal dysfunction that develops years before it becomes a diagnosis.

That is not necessarily your doctor's fault. The reimbursement model does not reward optimization. The short visit does not allow time for nuanced interpretation. And the reference ranges used by major labs are built to flag pathology, not to define what thriving looks like.

But the gap between "not sick" and "optimized" is where the most important health decisions of your life get made. Or missed entirely.

Here are the blood tests your doctor isn't running, what they reveal, and why the difference between "normal" and "optimal" matters.

ApoB: The Particle Count Missing From a Standard Lipid Panel

I test ApoB on every patient. No exceptions.

Your standard lipid panel measures LDL cholesterol, the amount of cholesterol riding inside LDL particles. That number can mislead you. Two people with identical LDL-C can have very different numbers of atherogenic particles in their blood. One is at low risk. The other is building plaque right now.

ApoB cuts through the noise. It is a protein that sits on the surface of every plaque-forming lipoprotein particle: LDL, VLDL, Lp(a). One ApoB molecule per particle. So your ApoB level is a direct particle count. Not an estimate. A count.

Sniderman and colleagues, in a 2019 narrative review in JAMA Cardiology, laid out the evidence that ApoB measures atherogenic risk more accurately than LDL-C or non-HDL cholesterol, because cholesterol can only enter the arterial wall inside an ApoB particle. Genetic evidence points the same way: Ference and colleagues (JAMA, 2019) showed that the cardiovascular benefit of lipid-lowering gene variants tracked with the change in ApoB rather than with LDL-C or triglycerides alone.

If you have never had yours tested, you are flying blind on your number one killer.

Where you want to be:

• Standard "normal": under 130 mg/dL
• Where longevity physicians aim: under 80 mg/dL, and lower for people at higher risk

ApoB is on every Rebel Health Alliance member's first panel. Book a 30-minute call to get yours run and read.

Fasting Insulin

Your doctor tests your blood sugar. It comes back normal. Great. But what if your pancreas had to scream to keep that number normal?

That is what fasting insulin tells you. How hard your body is working behind the scenes.

Joseph Kraft spent decades running oral glucose tolerance tests with insulin measured alongside glucose. When Crofts and colleagues re-examined the Kraft database (Diabetes Research and Clinical Practice, 2016), just over half of the people with completely normal glucose tolerance had hyperinsulinemia anyway. Their glucose looked fine. Their insulin did not. One honest caveat. Kraft measured insulin after a glucose load, and Crofts found that fasting insulin on its own had limited value for identifying hyperinsulinemia. Fasting insulin is the practical screen. When it reads borderline, the next step is insulin measured with a glucose challenge.

A fasting insulin of 18 uIU/mL is technically "normal" by many lab standards (the reference range often runs up to about 25). Metabolically, it is a warning. Your HOMA-IR at that level sits around 4, roughly double the upper end of what I consider optimal.

• Standard "normal": 2.6 to 24.9 uIU/mL
• Where you actually want to be: under 6 to 8 uIU/mL

Fasting insulin is one of the earliest warning signals of metabolic dysfunction, the root driver behind much of heart disease, type 2 diabetes, PCOS and fatty liver. Catch it early and nutrition, movement and sleep can bring it down. Catch it late and you are managing damage.

hs-CRP (High-Sensitivity C-Reactive Protein)

I have lost count of the times I have caught a smoldering inflammatory process with an hs-CRP when every other marker looked clean. A patient's labs came back pristine: lipids great, metabolic panel perfect, hormones balanced. Her hs-CRP was 4.2. That number sent us down a path that uncovered an autoimmune process nobody had been looking for.

It is one of my non-negotiables.

hs-CRP measures systemic inflammation. Your liver produces it in response to inflammatory signals from across your body. Some cardiologists order it for cardiac risk stratification. Most primary care physicians do not.

Here is how the common cut points read:

• Under 1.0 mg/L: low risk. This is where you want to live.
• 1.0 to 3.0 mg/L: moderate. Something is simmering.
• Over 3.0 mg/L: high, even though many lab reports will not flag it.

Chronic low-grade inflammation is tied to cardiovascular disease, cancer, neurodegeneration and metabolic dysfunction. Franceschi and colleagues coined the term "inflamm-aging" for exactly this in a 2000 paper in the Annals of the New York Academy of Sciences. An hs-CRP of 2.5 is "normal." It is also a slow burn.

The real value is not the number itself. It is what comes next: finding the source. Metabolic dysfunction. Poor sleep. Visceral fat. Dietary triggers. Chronic stress. Infections. You cannot do that detective work in a seven-minute visit.

Homocysteine

Homocysteine had a rough decade. Honestly, it got a raw deal.

The big B-vitamin trials found that supplementing with B vitamins did not cut cardiovascular events the way everyone hoped. In HOPE-2 (Lonn and colleagues, New England Journal of Medicine, 2006), folic acid plus B6 and B12 lowered homocysteine but did not reduce major cardiovascular events. VISP (Toole and colleagues, JAMA, 2004) found the same for recurrent stroke. Cardiologists moved on. Homocysteine fell off the radar.

Here is what got lost: the problem was with the intervention as a cardiac drug, not with the biomarker.

Homocysteine is an amino acid tied to methylation, a biochemical process your body uses for DNA repair, detoxification and neurotransmitter production. When it is elevated, your methylation machinery is not running right. And the brain data still has teeth: in the VITACOG trial (Smith and colleagues, PLoS One, 2010), two years of high-dose B vitamins slowed brain atrophy in older adults with mild cognitive impairment, and the effect was largest in people whose homocysteine started above 13 umol/L.

• Standard "normal": under 15 umol/L
• Optimal: under 8 umol/L

The workup comes first: B12 status, kidney function and thyroid all push homocysteine up. When it is a methylation problem, the fix is usually methylated B vitamins (methylfolate, methylcobalamin, B6) at doses your physician sets. Cheap. Effective at bringing the number down. But only if you know it is elevated in the first place.

Full Thyroid Panel (Not Just TSH)

Your doctor runs TSH. Maybe. That is it.

I saw this exact scenario recently. A patient came in exhausted, gaining weight, losing hair. Her PCP had tested TSH twice, both times "normal." We ran the full panel. Free T3 was at the bottom of the range. TPO antibodies were through the roof. She had been living with undiagnosed autoimmune thyroid disease for who knows how long.

Here is what should actually be ordered: TSH, Free T3, Free T4, Reverse T3, and thyroid antibodies (TPO and thyroglobulin).

TSH alone is like checking the thermostat and ignoring whether the furnace is producing heat. You can have a "normal" TSH of 3.5 while your Free T3, the active hormone your cells actually use, sits in the gutter. Meanwhile, Reverse T3 can be elevated, a sign your body is converting T4 down the inactive path instead of into the T3 your cells use. And thyroid antibodies could be quietly destroying the gland, signaling Hashimoto's thyroiditis years before TSH moves.

Ranges I aim for:

• TSH: 1.0 to 2.0 mIU/L (not the standard 0.5 to 4.5)
• Free T3: 3.0 to 4.0 pg/mL
• Free T4: 1.2 to 1.5 ng/dL
• Reverse T3: under 15 ng/dL
• TPO / TG antibodies: negative

This is not rare. In the Colorado Thyroid Disease Prevalence Study (Canaris and colleagues, Archives of Internal Medicine, 2000), 9.5% of more than 25,000 adults had an elevated TSH, much of it previously undetected. National survey data from Hollowell and colleagues (Journal of Clinical Endocrinology and Metabolism, 2002) put subclinical hypothyroidism at 4.3% of the U.S. population. Millions of people are told fatigue, weight gain, brain fog, hair loss and cold intolerance are "just part of getting older." Often they are not.

DHEA-S

Nobody talks about this one. They should.

DHEA is the most abundant steroid hormone in your body, a precursor to both testosterone and estrogen. DHEA-S is the sulfated storage form. Orentreich and colleagues (Journal of Clinical Endocrinology and Metabolism, 1984) measured it across nearly 1,500 people aged 11 to 89. Levels peak between ages 20 and 24 in men, 15 and 19 in women, then decline for the rest of your life, to roughly a fifth of peak by the eighth decade.

Your doctor does not test it. It is not on any standard panel. Most physicians do not think about hormones unless you walk in with overt symptoms.

Low DHEA-S is associated with reduced immune function, loss of muscle mass and lower energy. Once identified, it is straightforward to correct under a physician's eye; DHEA is a hormone precursor, not a multivitamin, and it is not for everyone. But nobody supplements what nobody tests.

• Where longevity physicians aim: the upper part of the age-adjusted range

Testosterone, Free Testosterone and SHBG

Let us clear something up. Testosterone matters for women too. Low testosterone in women contributes to fatigue, low libido, loss of muscle mass and low mood. It is almost never tested.

For men, here is the trap. Your doctor runs total testosterone, if you are lucky enough to get it ordered at all. It comes back at 450 ng/dL. "Normal." Case closed.

Except it is not. If your SHBG (sex hormone-binding globulin) is elevated, that 450 is misleading. SHBG binds testosterone and takes it out of circulation. Your free testosterone, the form your cells actually use, could be low while your total number looks fine on paper.

What should actually be ordered: total testosterone, free testosterone, SHBG, estradiol, LH, FSH.

Ranges I aim for (men):

• Total testosterone: 600 to 900 ng/dL (not the lab range of roughly 264 to 916)
• Free testosterone: 15 to 25 pg/mL
• SHBG: 20 to 40 nmol/L

Vitamin D (25-OH)

Vitamin D is not really a vitamin. It behaves like a steroid hormone. Ramagopalan and colleagues (Genome Research, 2010) mapped 2,776 binding sites for the vitamin D receptor across the human genome and found 229 genes whose expression changed in response to vitamin D, including genes linked to autoimmune disease.

Some PCPs order it. Many do not. And when they do, they see 30 ng/mL and call it "sufficient."

• Standard "sufficient": over 30 ng/mL
• Where I aim for health and performance: 50 to 80 ng/mL

Deficiency is common. Forrest and Stuhldreher (Nutrition Research, 2011) analyzed national survey data and found 41.6% of U.S. adults were deficient at 20 ng/mL or below. Many more are suboptimal.

Here is what drives me crazy about this one. The generic "take 1,000 IU" recommendation on the back of a supplement bottle. Dosing should be based on your actual blood level and body weight. Anything less is guessing.

The Metabolic Trifecta: HbA1c, Fasting Glucose and Fasting Insulin Together

Your doctor may run HbA1c or fasting glucose. Rarely both. Almost never with fasting insulin.

HbA1c reflects your average blood sugar over about three months. Fasting glucose reflects your blood sugar at one moment in time. Neither tells you how hard your pancreas is working to maintain those numbers. Fasting insulin does.

The complete metabolic picture requires all three:

• Fasting glucose: under 90 mg/dL (optimal), not just under 100
• HbA1c: under 5.4% (optimal), not just under 5.7%
• Fasting insulin: under 6 to 8 uIU/mL (optimal), not just under 25

I ran this exact panel on a man recently. Fasting glucose: 92. HbA1c: 5.5%. Every standard screening said "normal." His fasting insulin came back at 19. HOMA-IR at those numbers is roughly 4.3, well above the 1.0 to 2.0 I consider optimal. This person was not healthy. He was compensating. Left alone, that pattern carries real risk of type 2 diabetes, fatty liver and cardiovascular disease. We caught it. A standard panel never would have.

The Blood Tests Your Doctor Isn't Running: Normal Versus Optimal

The reference ranges on your lab report come from population data, and that population is not healthy. Those ranges describe the people who walked into the lab, not people who are thriving.

"Normal" means you fall within the range of a largely unhealthy population. That is it. It does not mean you are optimized for longevity, performance or disease prevention.

At Rebel Health Alliance, we use evidence-based optimal ranges, not population norms, to assess every biomarker. And we do not just test. Your physician builds a protocol from what the data shows, tracks your progress with follow-up labs at the same wholesale rates, and adjusts based on how your body responds.

What to Do With This Information

You have three options.

1. Ask your PCP to order these tests. Some will. Many will not, because most of these are not reimbursed as screening tests. If yours will, great. Bring this article with you.

1. Order the labs yourself through a direct-to-consumer service. You will get the data. You will still need a physician who can interpret it and act on it.

1. Work with a physician who tests, interprets and builds your protocol. That is what we do at Rebel Health Alliance. Every member starts with an initial panel of more than 100 biomarkers (billed separately at wholesale, about $450), including ApoB, Lp(a), fasting insulin, hs-CRP, homocysteine, a thyroid panel with Free T3, Free T4 and Reverse T3, DHEA-S, testosterone (free, bioavailable and total, with SHBG for men) and vitamin D, with access to more than 3,000 diagnostic tests from there. Thyroid antibodies are a cash-pay add-on your physician adds when your protocol calls for it. Your physician is on demand: message anytime, replies usually same day. On Rebel Peak, a CSCS strength coach and a registered dietitian program off the same bloodwork, with care coordinators booking the labs and appointments. See how it works.

The worst option is the one most people choose: get 15 markers tested once a year, hear "everything's normal," and assume silence means safety.

It does not.

Your health deserves better data and a physician who knows what to do with it. Book a 30-minute call to find out what your blood is actually telling you.

Frequently asked questions

Is ApoB better than an LDL cholesterol test?
Yes, for estimating cardiovascular risk. LDL-C measures cholesterol mass; ApoB counts the particles that actually carry it into the artery wall. Sniderman and colleagues (JAMA Cardiology, 2019) reviewed the evidence that ApoB tracks atherogenic risk more accurately than LDL-C or non-HDL cholesterol.

What blood tests should I ask my doctor for beyond the standard panel?
ApoB, Lp(a), fasting insulin, hs-CRP, homocysteine, a full thyroid panel (TSH, Free T3, Free T4, Reverse T3, TPO and thyroglobulin antibodies), DHEA-S, total and free testosterone with SHBG, and vitamin D 25-OH. The longevity lab tests post walks through each one in more depth. Most are inexpensive. The barrier is usually that they are not reimbursed as routine screening, not that they are exotic.

Why does my doctor say my labs are normal when I feel terrible?
Because "normal" means you fall inside a reference range drawn from the general population, not from people who are metabolically healthy. Those are not the same group. Feeling well and being inside that range are different things. Fasting insulin, Free T3 and hs-CRP are the three markers most likely to explain symptoms when everything else reads normal.

What is a good fasting insulin level?
Many labs call anything under 25 uIU/mL normal. I aim for under 6 to 8. Crofts and colleagues (2016) found that just over half of people with normal glucose tolerance in the Kraft database had elevated insulin anyway, which is why glucose and HbA1c alone miss early metabolic dysfunction.

How much does this kind of testing cost?
At Rebel Health Alliance the initial panel of more than 100 biomarkers runs through Quest Diagnostics at wholesale rates, about $450 (about $600 in New York State), billed separately from membership. Named diagnostics beyond the panel are cash-pay add-ons your physician recommends only when your protocol calls for them.

Dr. Alec Weir is the Chief Medical Officer at Rebel Health Alliance (https://rebelhealthalliance.io), a 100% virtual, physician-led longevity practice in all 50 states. This article is for education only and is not medical advice.