Why am I always tired even though my blood work is normal?

Free testosterone

SHBG (sex hormone-binding globulin) and albumin carry most of your testosterone. About 2% circulates free, the share that reaches your tissues. SHBG grips tightly, so when it runs high, a normal total can hide a low free level. Labs call 46 to 224 pg/mL normal. We want 105 to 224.

In a study of 3,369 European men aged 40 to 79, fatigue and limited physical vigor tracked with lower testosterone. The most specific signs were sexual, with fewer morning erections, lower desire, and weaker erections.

Sleep, food, strength training, and fat loss all move it. Fix Your Testosterone covers the full hormone chain.

Free T3

TSH, the standard thyroid screen, tells your thyroid to make T4. Your liver and other tissues convert T4 into T3, the active hormone that sets your metabolic pace. Stress, illness, and under-eating slow that conversion, so TSH can read normal while free T3 runs low.

In a Washington University study, adults who had eaten about 1,800 calories a day for six years on average had T3 levels about 20% lower than matched adults on a typical diet. Their TSH and T4 matched.

We want free T3 between 3.0 and 3.5 pg/mL, inside a lab range of 2.3 to 4.2. Eating enough for your training, with carbohydrate around your sessions, is usually the first fix.

Fasting insulin

A fasting insulin of 15 µIU/mL comes back normal. We want 2 to 5.

As your cells resist insulin, your pancreas makes more, so glucose can look normal for years while insulin climbs. In the Whitehall II study of 6,538 British civil servants, insulin sensitivity fell steeply in the five years before a diabetes diagnosis. Fasting glucose climbed sharply only in the last three.

High insulin locks stored fat in place, so you run on blood sugar and slump each time it drops. About 80% of the glucose cleared under insulin’s signal goes into muscle, so strength training is the first lever. Fix Your Metabolism goes marker by marker through the insulin side.

Ferritin

Ferritin is your stored iron. Your body uses iron to carry oxygen and make energy inside your cells. Stores run down well before hemoglobin falls, so a normal blood count can miss low iron.

Standard ranges start as low as 16 ng/mL. We want 45 to 79. The American Gastroenterological Association now uses 45 ng/mL as its cutoff for iron deficiency in patients with anemia, because the old cutoff of 15 missed about 4 in 10 cases.

In a man, low ferritin goes to your physician first. The usual cause is blood loss, most often from the gut. High ferritin climbs with inflammation and insulin resistance. Paired with high iron saturation, it goes to your physician too.

Vitamin B12

Labs flag B12 below about 200 pg/mL. We want it above 545. Your body needs B12 to make red blood cells and keep your nerves working. Running short can leave you tired, foggy, and weak, sometimes with tingling in your hands or feet.

Long-term use of metformin or a daily acid reducer lowers B12. Heavy drinking and a diet light on meat, fish, eggs, and dairy lower it too. If you take either medication, keep taking it as prescribed and bring your B12 result to the physician who manages it.

Two tired executives, opposite fixes

These two executives, composites of patterns we see all the time, show why we read the five markers together.

Two composite executives · Both panels read normal

Same low free testosterone, opposite causes

Marker and optimal range	Executive 1Trains hard, under-eats	Executive 2Client dinners, long days sitting
On a standard annual panel
TSH1.0-2.0 mIU/L	1.6, optimal	1.9, optimal
Fasting glucose75-86 mg/dL	77, optimal	96, above optimal
Usually left off
Free T33.0-3.5 pg/mL	2.6, below optimal	3.3, optimal
Fasting insulin2-5 µIU/mL	2.4, optimal	14, above optimal
Ferritin45-79 ng/mL	38, below optimal	210, above optimal
Vitamin B12545-1,100 pg/mL	390, below optimal	610, optimal
Total testosterone600-1,100 ng/dL	560, below optimal	390, below optimal
SHBG40-46 nmol/L	48, above optimal	24, below optimal
Free testosterone105-224 pg/mL	93, below optimal	93, below optimal
First fix	More food, carbs around training	Strength training and fat loss

OptimalBelow optimalAbove optimal

Composite examples built from patterns we see often. Every value sits inside the standard lab range, so both panels come back normal. Free testosterone is calculated from total testosterone, SHBG, and an albumin of 4.4 g/dL.

Executive 1 trains hard, eats once or twice a day, and drinks coffee until dinner. Low fuel pushed his SHBG up and his free T3 down.

Client dinners, drinks, and long days in a chair pushed Executive 2’s fasting insulin to 14. High insulin lowered his SHBG, which pulled his total testosterone down with it.

Both men land at 93 pg/mL of free testosterone for opposite reasons. The usual advice to eat less and train more would help Executive 2 and sink Executive 1.

Eating more can fix Executive 1’s fatigue without stalling fat loss. Luke, a 44-year-old doctor of physical therapy who runs a hospital department, ate about 45% more each day in his first 90 days with us. He went from 190 to 169 pounds and from a 38-inch waist to a 32.

What blood work can’t see

Rule out sleep apnea first. In a Wisconsin study, an estimated 82% of men with moderate to severe cases had never been diagnosed. If you snore, wake up unrefreshed, or fight sleep in meetings, ask your physician about a sleep study.

Short sleep shows up in your labs eventually. One week of five-hour nights cut daytime testosterone 10 to 15% in healthy young men.

Alcohol hits recovery first. In 4,098 Finnish employees wearing heart rate monitors, recovery in the first three hours of sleep fell about 9 percentage points after light drinking and 39 after heavy drinking. Our 222 Rule keeps alcohol in clients’ lives at two drinks, two days a week, finished at least two hours before bed.

Under-eating leaves you leaning on caffeine by mid-afternoon. Even six hours before bed, 400 mg of caffeine, about four cups of coffee, cut measured sleep by more than an hour in one study.

We read sleep, HRV, and recovery from your wearable, which catches these drains before your blood does.

The tests to ask for

Take this list to your next physical. Ask for each test by name and get the actual values back, so you can read them against the optimal ranges above.

Bring this to your next physical

The fatigue panel

Testosterone

• Total testosterone
• SHBG and albumin
• Free testosterone, calculated

Thyroid

• TSH
• Free T3 and free T4
• Reverse T3

Blood sugar

• Fasting insulin and fasting glucose
• HbA1c
• Triglycerides and HDL

Iron and red blood cells

• Ferritin
• Iron, TIBC, and transferrin saturation
• CBC with hemoglobin and MCV

Vitamins and inflammation

• Vitamin B12 and MMA
• Folate
• Vitamin D (25-OH)
• hs-CRP

Draw it right

1. Book an early-morning draw after fasting 10 to 12 hours, water only.
2. Skip hard training for two to three days before. Hard sessions can raise liver enzymes and creatinine for up to 72 hours.
3. Pause biotin a few days ahead. A common dose skewed 9 of 23 lab tests in a small JAMA study.
4. Retest at the same lab, at the same time of day.

When fatigue belongs with your physician

Coaching works in the gap between normal and optimal. These belong with your physician first.

• Fatigue with weight loss you can’t explain, fevers, or night sweats
• Chest pain or shortness of breath when you exert yourself
• Loud snoring with daytime sleepiness
• Low hemoglobin or low ferritin
• TSH outside the lab range
• Fasting glucose of 126 mg/dL or higher, or HbA1c of 6.5% or higher
• Low mood or lost interest in things you enjoy for more than two weeks

How fast energy comes back

Energy usually comes back before the lab markers move. The two men from the opening started with us in August.

Monthly scorecards · Onboarding to week eight

The two men from the top of this article

The insurance executive

• Energy2 →to 8 of 10110
• Resting heart rate77 →to 56 bpm
• Restful nights2 →to 5 a week
• Weight, month oneDown 11.3 lbs

The attorney

• Energy1 →to 7 of 10110
• Brain fog (10 is worst)10 →to 3110
• Restful nights0 →to 5 a week
• Weight, month oneDown 10 lbs

From each man's monthly scorecards in our client portal. Energy and brain fog are self-rated from 1 to 10. Weight change covers the first month.

Both had their blood work scored against optimal ranges, with nutrition targets built from it, weekly check-ins, and monthly scorecards. Our average client sees a 66% increase in energy in the first month.

Our online executive health coaching starts from 100+ biomarkers, so the first month goes straight at the markers draining you.