DRAFT
After Forty Feel
A Reader Dossier · Bloodwork at 45+

The 12 Labs Every Adult 45+ Should Run — and the Optimal Ranges Most Doctors Won't Tell You

The standard physical orders a sliver of what your insurance will pay for. This dossier covers the twelve markers we'd actually want, what they mean past 45, and the ranges that the longevity literature uses — not the ones printed on the lab slip.

Compiled by the After Forty Feel editorial team · Reviewed against AACE, Endocrine Society, Sniderman 2019, Berkeley HeartLab and UCLA CHN reference data.

Most "your bloodwork is normal" conversations end too soon. "Normal" on a lab report is a population reference range — the middle 95% of who showed up at that lab. It is not an optimal range, and it is rarely tuned for an adult past 45. What follows is the list we'd hand a friend.

For each marker: why it matters, what your lab will print as "normal," the tighter optimal target the longevity literature uses, the level at which we'd act, and the one question to bring to the consult. None of this replaces a clinician — it makes the conversation sharper.

Marker 01

HbA1c

A three-month average of your blood sugar — the single best early-warning marker for the slow drift into insulin resistance.

Standard range
4.0 – 5.6% (non-diabetic per ADA)
Optimal 45+
< 5.4% (AACE pre-diabetes prevention guidance, 2022)
Act at
5.5% or higher — even if "normal"
"My HbA1c is in the high-fives. Can we look at fasting insulin and a fructosamine before I'm officially pre-diabetic?"
Marker 02

ApoB (apolipoprotein B)

Counts the actual number of atherogenic particles in your blood — a far better cardiovascular risk marker than LDL-C alone (Sniderman 2019).

Standard range
< 130 mg/dL (lab default cut-off)
Optimal 45+
< 80 mg/dL (Sniderman, JAMA Cardiol. 2019); < 60 mg/dL if family history of early CVD
Act at
> 90 mg/dL — conversation about diet, then a statin / Repatha discussion
"My LDL is fine but my ApoB is over 90. What does the particle count actually mean for my 10-year risk?"
Marker 03

Fasting Insulin

Rises years before glucose does. Insulin resistance is the engine behind the cortisol-belly, the 3 p.m. crash, and most "I'm not eating that much" weight stories at 50.

Standard range
2.6 – 24.9 μIU/mL (lab default; uselessly wide)
Optimal 45+
< 6 μIU/mL fasting (UCLA Center for Human Nutrition reference; Kraft 1975 pattern)
Act at
> 8 μIU/mL — calculate HOMA-IR and discuss
"Can we add fasting insulin to the next draw and calculate HOMA-IR? I want to see this before glucose moves."
Marker 04

Free + Total Testosterone (men) / FSH + Estradiol (women)

The single most under-ordered set of labs in midlife. The complaints we hear — flat mood, fog, soft middle, dead libido — often map onto sex-hormone shifts well before a clinician thinks to test for them.

Standard range (M)
Total T 264 – 916 ng/dL (huge; age-blind)
Optimal M, 45+
Total T 600 – 900 ng/dL; Free T 15 – 25 pg/mL (Endocrine Society 2018 + Mulhall 2018)
Standard range (F)
FSH 4.7 – 21.5 mIU/mL (pre-meno); rises in transition
Pattern, women
FSH > 25 mIU/mL with estradiol < 30 pg/mL = post-menopausal pattern (NAMS 2022)
Act at
Symptoms + Total T < 400 (M); FSH > 25 + symptoms (F)
"Given the symptoms, can we run a full sex-hormone panel before defaulting to an antidepressant?"
Marker 05

Full Thyroid Panel (TSH, Free T3, Free T4)

TSH alone misses subclinical hypothyroidism. Free T3 is the active hormone — and it's the one nobody orders.

Standard TSH range
0.45 – 4.50 mIU/L
Optimal TSH 45+
1.0 – 2.5 mIU/L (AACE 2012; Wartofsky 2005 narrower-window argument)
Optimal Free T3
Upper third of lab range (typically > 3.2 pg/mL)
Act at
TSH > 2.5 with symptoms; or low Free T3 regardless of TSH
"Can we add Free T3, Free T4, and antibodies to the TSH? My energy and recovery aren't matching the 'normal' number."
Marker 06

Vitamin D (25-OH)

Underrated for bone, mood, immune, and — in women — the perimenopause transition. The lab cutoff is set so low that most adults clear it on paper while running suboptimal.

Standard range
30 – 100 ng/mL "sufficient"
Optimal 45+
50 – 80 ng/mL (Endocrine Society Clinical Practice Guideline 2011, reaffirmed)
Act at
< 40 ng/mL — supplement 4,000-5,000 IU + K2, retest in 90 days
"My 25-OH is in the thirties. Can I start 5,000 IU + K2 and recheck in three months before this becomes a bone-density problem?"
Marker 07

Ferritin

Iron stores. Women lose ferritin every month until they don't; once they don't, it climbs. Both ends matter past 45.

Standard range
F: 11 – 307 ng/mL  ·  M: 24 – 336 ng/mL
Optimal 45+
50 – 150 ng/mL (Berkeley HeartLab cardiovascular reference)
Act at
< 50 ng/mL: iron + Vit C ·   > 200 ng/mL: investigate inflammation / hemochromatosis
"My ferritin is under 50 even though my hemoglobin is normal. Should we treat the iron stores, not just the count?"
Marker 08

hs-CRP

High-sensitivity C-reactive protein. The cheapest, fastest read on chronic low-grade inflammation — the engine behind a lot of midlife disease.

Standard range
< 3.0 mg/L "low CV risk"
Optimal 45+
< 1.0 mg/L (Ridker, JUPITER trial; AHA/CDC 2003 cut-points)
Act at
> 1.5 mg/L sustained — look for visceral fat, gum disease, hidden infection, autoimmune
"My hs-CRP is between 1.5 and 3. What hidden inflammation source should we rule out before this becomes a heart conversation?"
Marker 09

Lipid Panel with Particle Size (NMR or ion-mobility)

The standard panel is a 1980s tool. NMR particle profiles — LDL-P, small dense LDL, Lp(a) — tell you whether the cholesterol number on the slip actually carries risk.

Standard LDL-C
< 100 mg/dL "optimal"
Optimal LDL-P 45+
< 1,000 nmol/L (Berkeley HeartLab NMR reference)
Lp(a)
< 30 mg/dL (genetic; test once, ever, per ACC 2018)
Act at
LDL-P > 1,300 nmol/L; small-dense LDL > 200 nmol/L; Lp(a) > 50 mg/dL
"My LDL is borderline. Can we order an NMR or ion-mobility panel to see particle size and Lp(a) before deciding on a statin?"
Marker 10

DHEA-S

An adrenal hormone that quietly underwrites energy, libido, mood, and bone. Declines about 2% per year after 30 — faster under chronic stress.

Standard range
M: 80 – 560 μg/dL · F: 35 – 430 μg/dL (age-blind)
Optimal 45+ (M)
250 – 450 μg/dL (Endocrine Society 2014 androgen guidance)
Optimal 45+ (F)
150 – 300 μg/dL
Act at
Below midpoint with persistent fatigue — investigate HPA-axis
"My DHEA-S is at the bottom of 'normal' for my age. Is this an HPA-axis conversation, or just a number?"
Marker 11

RDW (red cell distribution width)

The most underused marker on your CBC. A rising RDW — even within "normal" — is one of the strongest all-cause mortality signals in the literature.

Standard range
11.5 – 14.5%
Optimal 45+
< 13.0% (Patel 2010, Arch Intern Med; Felker 2007 mortality data)
Act at
> 13.5% — check B12, folate, iron, inflammation
"My CBC is 'normal' but my RDW is creeping up. What's behind it — nutrient, marrow, or inflammation?"
Marker 12

Homocysteine

Methylation marker tied to cardiovascular and cognitive risk. Cheap to lower with B-vitamins if it's high. Almost never ordered.

Standard range
< 15 μmol/L "normal"
Optimal 45+
< 8 μmol/L (VITACOG cognitive-decline data; AHA cardiovascular guidance)
Act at
> 9 μmol/L — methylated B-12, B-6, folate, retest in 90 days
"Can we add homocysteine? Given my family history, I want to see methylation before we talk about anything else cardiovascular."
Take it deeper

Want the deeper Decoder?

The $19 Bloodwork Decoder walks through 8 follow-up scenarios when these come back yellow — the "your number is fine, but…" conversations. What the next test should be, what to actually change, and which letter to read next.

$19 · one-time, PDF + interactive web companion
Get The Bloodwork Decoder

Sources & Further Reading

  1. Sniderman AD, et al. "Apolipoprotein B Particles and Cardiovascular Disease." JAMA Cardiology, 2019.
  2. Endocrine Society. "Testosterone Therapy in Men With Hypogonadism: Clinical Practice Guideline." 2018.
  3. AACE / ACE. "Clinical Practice Guidelines for the Diagnosis and Management of Dyslipidemia and Prevention of Cardiovascular Disease." 2017, updated 2022.
  4. Berkeley HeartLab NMR Lipoprotein Reference Ranges, technical documentation.
  5. UCLA Center for Human Nutrition — reference ranges for fasting insulin and HOMA-IR.
  6. Endocrine Society. "Evaluation, Treatment, and Prevention of Vitamin D Deficiency." Clinical Practice Guideline, 2011 (reaffirmed).
  7. Ridker PM, et al. JUPITER trial. N Engl J Med, 2008.
  8. Patel KV, et al. "Red Cell Distribution Width and Mortality." Arch Intern Med, 2010.
  9. de Jager J, et al. VITACOG trial (homocysteine, B-vitamins, cognitive decline). 2010-2014.
  10. North American Menopause Society (NAMS) 2022 hormone therapy position statement.

Editorial dossier. Educational use only. Not medical advice — bring this to your physician, not in place of them.

After Forty Feel · afterfortyfeel.com · Independent. Reader-funded. No supplement-brand sponsorships.