Metabolic Health Markers to Track After 40: Complete Guide

Metabolic Health Markers to Track After 40: Complete Guide

Here’s a statistic that should concern you:

88% of adults in the UK have at least one marker of poor metabolic health.

That means only 12% of people have optimal:

• Blood sugar control
• Insulin sensitivity
• Lipid levels
• Blood pressure
• Waist circumference

If you’re over 40 and not actively tracking these markers, you’re almost certainly in the 88%.

And here’s why that matters:

Poor metabolic health doesn’t just increase your risk of Type 2 diabetes and heart disease. It directly impacts:

• Daily energy levels (afternoon crashes, brain fog)
• Cognitive performance (processing speed, memory)
• Physical stamina (climbing stairs, endurance)
• Work capability (sustained focus, stress resilience)
• Quality of life (mood, sleep, vitality)

By the time symptoms appear, significant damage has occurred.

This article explains:

• The 12 metabolic markers every adult over 40 should track
• What “normal” vs. “optimal” actually means
• How to interpret your results
• Evidence-based interventions when markers are suboptimal
• How often to test (hint: not just once a year)

Let’s start with the most important marker that most people never test.

Marker #1: Fasting Insulin (The Most Underutilized Test)

What it measures: How much insulin your pancreas produces to manage blood sugar

Why it matters: Insulin resistance develops 10-15 years before a Type 2 diabetes diagnosis. Fasting insulin catches it early—fasting glucose doesn’t.

How the process works:

Healthy metabolism:

1. You eat carbohydrates
2. Blood sugar rises
3. The pancreas releases a small amount of insulin
4. Cells absorb glucose efficiently
5. Blood sugar returns to normal
6. Insulin drops

Early insulin resistance (often starts at age 35-45):

1. You eat carbohydrates
2. Blood sugar rises
3. Cells don’t respond well to insulin
4. The pancreas produces MORE insulin to compensate
5. Blood sugar eventually normalizes (looks fine on tests)
6. But insulin remains chronically elevated

This is the hidden phase. Your doctor tests fasting glucose—it’s normal. So you’re told you’re fine. But your fasting insulin is 15-20 μIU/mL (should be <5), meaning you’re already insulin resistant.

Optimal Ranges:

Fasting Insulin (after 8-12 hour fast):

Range	Status	What It Means
<5 μIU/mL	Optimal	Excellent insulin sensitivity
5-10 μIU/mL	Acceptable	Slight insulin resistance beginning
10-15 μIU/mL	Concerning	Moderate insulin resistance
>15 μIU/mL	Poor	Significant insulin resistance

NHS “normal” range: 3-25 μIU/mL
Optimal for longevity: <5 μIU/mL

See the problem? You can have insulin of 20 and be told it’s “normal” when it’s actually indicating severe metabolic dysfunction.

How to Optimize:

If fasting insulin 10-15 μIU/mL:

• Time-restricted eating (12-14-hour overnight fast)
• Reduce refined carbohydrates
• Increase protein to 1.6-2.0g per kg bodyweight
• Add resistance training 3x weekly
• Consider berberine 500mg 2x daily

If fasting insulin >15 μIU/mL:

• Everything above, plus:
• Consider metformin (prescription—discuss with GP)
• Increase fasting window to 14-16 hours
• Prioritize carbs around exercise only
• Add 20-30 minutes of daily walking after meals
• Monitor closely (test every 3 months)

Evidence: Studies show these interventions can reduce fasting insulin by 30-50% in 12 weeks.

Marker #2: HbA1c (3-Month Blood Sugar Average)

What it measures: Percentage of hemoglobin coated with glucose over the past 3 months

Why it matters: Single fasting glucose is a snapshot. HbA1c shows your average blood sugar control over 12 weeks—much more reliable.

How it works:

• Red blood cells live ~120 days
• Glucose in your bloodstream gradually attaches to hemoglobin
• Higher average blood sugar = more glucose-coated hemoglobin
• Blood test measures the percentage of hemoglobin that’s glycated

Optimal Ranges:

HbA1c:

Range	Status	Risk Level
<5.4%	Optimal	Lowest risk of complications
5.4-5.6%	Acceptable	Slight increase in risk
5.7-6.4%	Prediabetes	High risk of progression
≥6.5%	Type 2 Diabetes	Requires medical management

NHS diagnosis:

• Prediabetes: 42-47 mmol/mol (6.0-6.4%)
• Diabetes: ≥48 mmol/mol (≥6.5%)

Optimal for longevity: <5.4% (36 mmol/mol)

Why Even 5.7% Is Problematic:

Research shows that every 0.1% increase in HbA1c above 5.4% increases:

• Cardiovascular disease risk by 6%
• Cognitive decline risk by 8%
• Microvascular damage (eyes, kidneys, nerves)

You don’t need to be diabetic for elevated blood sugar to damage your body.

How to Optimize:

If HbA1c 5.5-5.7%:

• Eliminate added sugars completely
• Reduce overall carbohydrate intake (especially refined carbs)
• Never eat carbs alone (always pair with protein/fat)
• Walk 10-15 minutes after every meal
• Add cinnamon (2-3g daily—modest blood sugar benefit)

If HbA1c 5.7-6.4% (Prediabetes):

• Everything above, plus:
• Consider a low-carb or ketogenic diet (trial 12 weeks)
• Berberine 500mg 3x daily (comparable to metformin in studies)
• Resistance training 3-4x weekly (increases insulin sensitivity)
• Monitor every 3 months
• Discuss metformin with GP

If HbA1c ≥6.5% (Diabetes):

• Medical management required
• Work with a GP or endocrinologist
• All lifestyle interventions above remain critical
• Medication likely necessary

Marker #3: Triglycerides (And the Trig/HDL Ratio)

What it measures: Fat molecules circulating in your blood

Why it matters: High triglycerides indicate poor carbohydrate metabolism and insulin resistance, often years before HbA1c rises.

What causes elevated triglycerides:

• Excess carbohydrate intake (especially fructose)
• Alcohol consumption
• Insulin resistance
• Sedentary lifestyle

Not primarily caused by dietary fat (common misconception).

Optimal Ranges:

Triglycerides (fasting):

Range	Status	Assessment
<100 mg/dL (<1.1 mmol/L)	Optimal	Excellent metabolic health
100-150 mg/dL (1.1-1.7 mmol/L)	Acceptable	Monitor, room for improvement
150-200 mg/dL (1.7-2.3 mmol/L)	Elevated	Indicates insulin resistance
>200 mg/dL (>2.3 mmol/L)	High	Significant metabolic dysfunction

NHS “normal”: <2.3 mmol/L (200 mg/dL)
Optimal: <1.1 mmol/L (100 mg/dL)

The Critical Ratio: Triglycerides/HDL

This ratio is a powerful predictor of insulin resistance and cardiovascular risk.

Calculate:
Triglycerides (mg/dL) ÷ HDL (mg/dL)

Or in UK units:
(Triglycerides in mmol/L × 88.5) ÷ (HDL in mmol/L × 38.7)

Optimal Ratio:

• <2.0 = Excellent insulin sensitivity
• 2.0-3.0 = Mild insulin resistance
• 3.0-5.0 = Moderate insulin resistance
• 5.0 = Severe insulin resistance

Example:

• Triglycerides: 150 mg/dL
• HDL: 50 mg/dL
• Ratio: 150 ÷ 50 = 3.0 (moderate insulin resistance)

How to Optimize:

If triglycerides are 100-150 mg/dL:

• Reduce refined carbohydrates significantly
• Eliminate added sugars and fructose
• Limit alcohol to 1-2 drinks per week maximum
• Omega-3: 2-3g EPA+DHA daily
• Add 30 minutes of daily aerobic exercise

If triglycerides >150 mg/dL:

• Everything above, plus:
• Consider a low-carb diet (trial 12 weeks)
• Eliminate alcohol completely (temporarily)
• Increase omega-3 to 4g daily
• Add resistance training 3x weekly
• Consider niacin (nicotinic acid) 500mg—discuss with pharmacist first
• Retest in 3 months

Evidence: Low-carb diets can reduce triglycerides by 30-50% in 12 weeks.

Marker #4: HDL Cholesterol (The “Good” Cholesterol)

What it measures: High-density lipoprotein—carries cholesterol away from arteries back to liver

Why it matters: Low HDL is an independent risk factor for cardiovascular disease and indicates poor metabolic health.

Optimal Ranges:

HDL Cholesterol:

Gender	Optimal	Acceptable	Low (Concerning)
Men	>55 mg/dL (>1.4 mmol/L)	40-55 mg/dL	<40 mg/dL (<1.0 mmol/L)
Women	>65 mg/dL (>1.7 mmol/L)	50-65 mg/dL	<50 mg/dL (<1.3 mmol/L)

NHS guidelines flag HDL <1.0 mmol/L (men) or <1.3 mmol/L (women) as concerning.

But optimal is significantly higher.

What Lowers HDL:

• Sedentary lifestyle (most significant factor)
• Smoking
• Obesity (especially visceral fat)
• Refined carbohydrates
• Trans fats
• Genetic factors (less common)

How to Optimize:

If HDL 40-55 mg/dL (men) or 50-65 mg/dL (women):

• Aerobic exercise 150 minutes per week minimum (raises HDL 5-10%)
• Resistance training 2-3x weekly
• Omega-3: 2-3g EPA+DHA daily
• Moderate alcohol (1 drink daily may raise HDL slightly, but trade-offs)
• Lose visceral fat if elevated waist circumference

If HDL <40 mg/dL (men) or <50 mg/dL (women):

• Everything above, more aggressively
• Increase exercise to 200+ minutes per week
• Consider niacin supplementation (discuss with healthcare provider)
• Eliminate trans fats completely
• Focus intensely on visceral fat loss

Evidence: Regular aerobic exercise can increase HDL by 5-15% in 12 weeks.

Marker #5: ApoB (Apolipoprotein B)

What it measures: Number of atherogenic (artery-clogging) particles in your blood

Why it’s better than standard cholesterol:

• Standard test: Measures cholesterol content
• ApoB: Measures particle number (more predictive of cardiovascular risk)

The difference matters:

Two people with same total cholesterol (200 mg/dL):

• Person A: Large, fluffy LDL particles → ApoB 80 mg/dL → Low risk
• Person B: Small, dense LDL particles → ApoB 130 mg/dL → High risk

ApoB catches this difference. Standard cholesterol doesn’t.

Optimal Ranges:

ApoB:

Range	Status	Risk Level
<80 mg/dL	Optimal	Lowest cardiovascular risk
80-100 mg/dL	Acceptable	Moderate risk
100-130 mg/dL	Elevated	High risk
>130 mg/dL	Very High	Very high risk, intervention needed

Most UK labs don’t test ApoB routinely—you may need to request it specifically or use private testing.

How to Optimize:

If ApoB 80-100 mg/dL:

• Increase soluble fiber (10-15g from oats, beans, psyllium)
• Omega-3: 2-3g EPA+DHA daily
• Plant sterols: 2g daily (reduces LDL particle number)
• Regular exercise (both aerobic and resistance)

If ApoB >100 mg/dL:

• Everything above, plus:
• Consider low-carb or Mediterranean diet
• Increase omega-3 to 4g daily
• Discuss statin therapy with GP (especially if family history)
• Consider PCSK9 inhibitors if very high and statin-intolerant

• Eliminate trans fats, reduce saturated fat moderately

Marker #6: hsCRP (High-Sensitivity C-Reactive Protein)

What it measures: Systemic inflammation in your body

Why it matters: Chronic low-grade inflammation (“inflammaging”) drives:

• Cognitive decline
• Cardiovascular disease
• Insulin resistance
• Accelerated aging
• Reduced work capability

It’s the underlying mechanism of most age-related decline.

Optimal Ranges:

hsCRP:

Range	Status	Risk Level
<1.0 mg/L	Optimal	Low inflammation, low CV risk
1.0-3.0 mg/L	Moderate	Moderate inflammation, elevated CV risk
>3.0 mg/L	High	High inflammation, high CV risk
>10 mg/L	Very High	Acute inflammation (infection, injury)

If hsCRP >10 mg/L, likely acute infection/illness—retest when healthy.

What Causes Elevated hsCRP:

• Obesity (especially visceral fat)
• Poor diet (refined carbs, trans fats, excess omega-6)
• Sedentary lifestyle
• Smoking
• Poor sleep
• Chronic stress
• Gut dysbiosis
• Dental disease (gum inflammation)

How to Optimize:

If hsCRP 1.0-3.0 mg/L:

• Omega-3: 2-3g EPA+DHA daily (reduces hsCRP by 20-30%)
• Mediterranean diet pattern
• Regular exercise (150 minutes weekly)
• Optimize sleep (7-9 hours)
• Manage stress (meditation, yoga)
• Consider curcumin 500-1,000mg daily

If hsCRP >3.0 mg/L:

• Everything above, more intensely
• Investigate underlying causes (gut health, dental, chronic infections)
• Eliminate processed foods completely
• Increase omega-3 to 4g daily
• Add polyphenols (green tea, berries, dark chocolate)
• Consider an elimination diet to identify food triggers
• Retest in 8-12 weeks

Evidence: Combined omega-3 supplementation and Mediterranean diet can reduce hsCRP by 30-40% in 12 weeks.

Marker #7: Waist Circumference (The Simplest, Most Powerful)

What it measures: Visceral (abdominal) fat accumulation

Why it matters: Visceral fat is metabolically active—it produces inflammatory cytokines, worsens insulin resistance, and increases cardiovascular risk.

More predictive of health than BMI.

How to Measure:

1. Stand straight, breathe normally
2. Measure at belly button level (not the narrowest point)
3. Tape parallel to the floor, snug but not compressing
4. Measure at end of normal exhale

Optimal Ranges:

Waist Circumference:

Gender	Optimal	Acceptable	High Risk
Men	<94 cm (37 in)	94-102 cm	>102 cm (40 in)
Women	<80 cm (31.5 in)	80-88 cm	>88 cm (35 in)

Every 5 cm above optimal increases metabolic disease risk by ~20%.

How to Optimize:

If above optimal but below high-risk:

• Caloric deficit 300-500 calories daily
• Prioritize protein (40g per meal)
• Resistance training 3x weekly (preserves muscle)
• Daily walking 10,000 steps
• Eliminate liquid calories (sodas, juices)
• Sleep 7-9 hours (poor sleep increases visceral fat)

If in high-risk range:

• Everything above, more aggressively
• Consider time-restricted eating (12-14 hour fast)
• Track food intake rigorously (hidden calories common)
• Add HIIT training 2x weekly (targets visceral fat)
• Address emotional eating/stress eating patterns
• Consider professional support (dietitian, therapist)

Evidence: Combining diet, exercise, and sleep optimization can reduce waist circumference by 5-10 cm in 12 weeks.

💡Markers (Brief Overview)

Marker #8: Fasting Glucose

Optimal: <90 mg/dL (5.0 mmol/L)
Acceptable: 90-100 mg/dL
Prediabetic: 100-125 mg/dL
Diabetic: ≥126 mg/dL

Less sensitive than fasting insulin or HbA1c, but still valuable.

Marker #9: Liver Enzymes (ALT, AST)

Why it matters: Non-alcoholic fatty liver disease (NAFLD) affects 25% of adults over 40, driven by metabolic dysfunction.

Optimal ALT: <25 U/L (men), <20 U/L (women)
NHS “normal”: <40 U/L

If elevated: Address insulin resistance, lose visceral fat, eliminate alcohol, and increase omega-3.

Marker #10: Uric Acid

Why it matters: Elevated uric acid indicates metabolic dysfunction and increases gout, kidney stones, and cardiovascular risk.

Optimal: 4.0-6.0 mg/dL (240-360 μmol/L)
High: >7.0 mg/dL (>420 μmol/L)

Driven by: Fructose consumption, alcohol, insulin resistance, and purine-rich foods.

Optimization: Reduce fructose, limit alcohol, increase hydration, and consider tart cherry extract.

Marker #11: Homocysteine

Why it matters: Elevated homocysteine damages blood vessels, increasing the risk of cardiovascular and cognitive decline.

Optimal: <8 μmol/L
Acceptable: 8-10 μmol/L
Elevated: >10 μmol/L

Driven by: B-vitamin deficiencies (B6, B12, folate), genetics (MTHFR mutation).

Optimization: B-complex supplement (methylated forms if MTHFR positive), increase leafy greens.

Marker #12: Vitamin D

Why it matters: Affects immune function, bone health, mood, insulin sensitivity, and longevity.

Optimal: 100-150 nmol/L (40-60 ng/mL)
NHS “sufficient”: >50 nmol/L
Deficient: <50 nmol/L

Most UK residents are deficient.

Optimization: 4,000 IU daily year-round in the UK climate. Retest every 6 months.

How Often to Test

Initial baseline (if never tested comprehensively):

• Get all 12 markers
• Establish your starting point
• Identify areas needing intervention

Follow-up testing:

Every 3 months (if optimizing suboptimal markers):

• Fasting insulin
• HbA1c
• Lipids (trig, HDL, ApoB)
• hsCRP

Every 6-12 months (if markers are optimal):

• Full panel repeat
• Ensure optimization maintained
• Catch early decline

Annually (minimum if “healthy”):

• Complete metabolic panel
• Never go >12 months without testing

Getting These Tests in the UK

NHS Testing (Free via GP):

Usually available:

• HbA1c, fasting glucose
• Lipids (total cholesterol, HDL, triglycerides)
• Liver enzymes (ALT, AST)
• Basic metabolic panel

Rarely available on the NHS:

• Fasting insulin
• ApoB
• hsCRP
• Homocysteine

Private Testing Options:

Medichecks (medichecks.com)

• Comprehensive metabolic panels
• £100-300 depending on markers
• Home blood draw kits available

Thriva (thriva.co)

• Finger-prick tests
• £50-150
• Good for basic markers

Randox Health (randoxhealth.com)

• Comprehensive testing
• Walk-in clinics (London, Manchester, Belfast)
• £200-400 for full metabolic panel

My recommendation: Get NHS tests annually. Fill gaps with private testing (fasting insulin, ApoB, and hsCRP are worth paying for).

Interpreting Your Results: The Big Picture

Don’t fixate on single markers.

Look for patterns:

Pattern #1: Insulin Resistance Cluster

• Fasting insulin >10 μIU/mL
• HbA1c >5.5%
• Triglycerides >150 mg/dL
• HDL <50 mg/dL
• Waist circumference elevated

Action: Prioritize insulin sensitivity (diet, exercise, time-restricted eating, berberine/metformin).

Pattern #2: Inflammatory Profile

• hsCRP >2.0 mg/L
• Elevated liver enzymes
• High uric acid
• Suboptimal HDL

Action: Anti-inflammatory protocol (omega-3, Mediterranean diet, gut health optimization, stress management).

Pattern #3: Cardiovascular Risk Cluster

• ApoB >100 mg/dL
• Triglycerides >150 mg/dL
• HDL <40/50 mg/dL
• hsCRP >1.5 mg/L

Action: Aggressive risk reduction (diet, exercise, omega-3, consider statin if high risk).

The Metabolic Health Protocol for Adults Over 40

If markers are optimal (maintain):

Daily:

• 40g protein per meal (3 meals)
• 35-40g fiber
• Omega-3: 2g EPA+DHA
• Vitamin D: 4,000 IU
• Magnesium: 300-400mg

Weekly:

• Resistance training: 3x
• Aerobic exercise: 150 minutes
• 7-9 hours sleep nightly
• <2 alcohol servings

Quarterly:

• Retest key markers
• Adjust protocol as needed

If markers are suboptimal (optimize):

Implement targeted interventions:

• Address insulin resistance aggressively
• Reduce inflammation systematically
• Optimize body composition
• Support liver function
• Consider therapeutic supplementation (berberine, niacin, etc.)

Test every 3 months until markers are normalized, then maintain.

Why This Matters for Your Future

Your metabolic health at 50 predicts your capability at 70.

If your markers are suboptimal now:

• Cognitive decline accelerates
• Energy levels deteriorate
• Chronic disease risk skyrockets
• Work capability diminishes
• Quality of life declines

But metabolic dysfunction is reversible if caught early.

The interventions are straightforward:

• Diet optimization
• Regular exercise
• Strategic supplementation
• Sleep prioritization
• Stress management

The difference between someone who optimizes metabolic health at 45 vs. someone who ignores it is dramatic by age 65:

Person who optimized:

• Sharp cognition
• Stable energy
• Physical capability
• Disease-free
• Work-capable into 70s

Person who ignored it:

• Cognitive decline
• Chronic fatigue
• Type 2 diabetes, cardiovascular disease
• Physically limited
• Forced retirement at 60

The trajectory diverges based on what you do today.

Your Next Steps

This week:

1. Request metabolic panel from GP (get what’s available free)
2. Order private testing for markers NHS won’t cover (fasting insulin, ApoB, hsCRP)
3. Measure waist circumference (costs nothing, highly predictive)

Within 2 weeks: 4. Get blood drawn and receive results 5. Compare your results to optimal ranges (not just “normal”) 6. Identify areas needing intervention

Within 1 month: 7. Implement targeted protocols based on your specific markers 8. Track progress weekly (energy, symptoms, waist circumference) 9. Schedule follow-up testing (3 months if suboptimal, 12 months if optimal)

Metabolic health isn’t complicated. It just requires:

• Knowing your numbers
• Understanding what they mean
• Taking action when needed
• Retesting to verify improvement

You’re not trying to achieve perfection. You’re trying to avoid preventable decline.

References

1. Kraft JR. “Diabetes Epidemic & You.” Trafford Publishing, 2008.
2. Reaven GM. “The insulin resistance syndrome: definition and dietary approaches to treatment.” Annual Review of Nutrition 2005;25:391-406.
3. Sniderman AD, et al. “Apolipoprotein B Particles and Cardiovascular Disease.” JAMA 2019;321(13):1290-1291.
4. Ridker PM. “C-reactive protein and the prediction of cardiovascular events among those at intermediate risk.” Journal of the American College of Cardiology 2007;49(21):2129-2138.
5. Klein S, et al. “Waist circumference and cardiometabolic risk.” Diabetes Care 2007;30(6):1647-1652.

About the Author

Dele Abudu is a GPhC-registered pharmacist and founder of Morlongevity. He specializes in metabolic health optimization and evidence-based longevity protocols for adults over 40 who need sustained performance and vitality.

This article is for educational purposes and does not constitute medical advice. Always consult with a qualified healthcare provider before making changes to your health regimen or interpreting blood test results.