For the last 15 years, I’ve been tracking my own blood tests, building trends, and trying to make sense of the numbers but hardly any success. Now as an engineer, I’m approaching it like a cause and effect. Why does high blood sugar affect cholesterol? How does one spike influence arteries, kidneys, and eyes? And why do medications sometimes need higher doses over time?
This domain is completely new to me. So, I had to rely on internet searches, AI tools, and reliable YouTube channels to piece things together. I may be (most likely) incorrect in parts. Still, I wanted a version anchored in my current understanding to see where it deviates from medical science and build upon it. Journaling helps me uncover my own shortcomings in comprehension, and this is one of those attempts to reason from first principles.
Over the years, I’ve realized that when you strip away jargon and look at biology through the lens of systems and feedback loops, it starts to make intuitive sense, at least an engineer’s way of thinking :-). I’m trying to connect the dots between sugar, cholesterol, and organ health such as Kidney, Eyes, from a cause-and-effect perspective
1. The Body’s Energy Highway: Glucose
Our cells need energy, and carbohydrates (from the food we eat) are the primary fuel source. Carbs are converted into glucose. The body keeps blood glucose in a narrow range:
- Too low: Cells starve, and we feel weak.
- Too high: Sugar molecules start sticking to proteins and fats, a process called glycation.
Insulin, a hormone from the pancreas, acts as the key that helps cells absorb glucose. But when the system gets overloaded, or cells stop responding properly, this leads to insulin resistance
2. What Is Insulin Resistance?
Insulin resistance is when cells become less responsive to insulin. Pancreas compensates by producing more insulin, so even if blood sugar looks “normal,” insulin levels are high → an early sign of trouble. Over time, this overdrive causes both insulin and glucose to rise together, leading to cellular damage, fat buildup, and inflammation.
3. How to Identify Insulin Resistance
Fasting Insulin Test
- Measures insulin after fasting 8–12 hours.
- Normal: <10 µIU/mL
- 15–20 suggests hidden resistance even if glucose seems normal.
HOMA-IR (Homeostatic Model Assessment)
- <2 → normal
- 2–2.9 → early resistance
- ≥3 → significant resistance
Fasting Glucose & HbA1c
- Glucose: <100 mg/dL (normal), 100–125 (prediabetic), ≥126 (diabetic)
- HbA1c: <5.7% (normal), 5.7–6.4% (prediabetic), ≥6.5% (diabetic)
Triglyceride(TG)/HDL Ratio
- <2 → good
- 2–4 → moderate
- 4 → high likelihood of resistance
4. The Chain Reaction: From Sugar to Organ Damage
a. Blood Vessels and Cholesterol
Step 1: Endothelial damage
- High glucose reacts with proteins and fats to form Advanced Glycation End-products (AGEs).
- AGEs damage the endothelium, the smooth lining of blood vessels.
- Once roughened, blood flow is less smooth, and inflammation increases.
Step 2: LDL trapping
- Immune cells rush in to repair the damage, but LDL (bad cholesterol) gets trapped and oxidized.
- Oxidized LDL triggers more inflammation.
Step 3: Plaque formation
- Fat, immune cells, and dead tissue accumulate into plaques, narrowing arteries and reducing blood flow.
Step 4: Clotting and stroke risk
- Plaques can rupture, forming blood clots.
- If a clot blocks the arteries:
- Heart → heart attack
- Brain → stroke
In short: high sugar → AGEs → damaged vessels → LDL oxidation → plaque buildup → risk of heart attack/stroke.
b. Kidneys
I always heard that high diabetic levels can impact the Kidneys and eye, but how? The kidneys are the body’s filtration system, removing waste while keeping nutrients:
- Glucose overload: Nephrons (filtering units) work harder under high sugar, and thus increasing internal pressure.
- Glycation & damage: AGEs weaken the filtering membranes.
- Protein leakage: Albumin leaks into urine (microalbuminuria or in simple terms albumin), an early sign of kidney stress.
- Scarring: Chronic high sugar -> causes inflammation and fibrosis → chronic kidney disease.
c. Eyes
The retina in our eyes relies on tiny blood vessels:
- Capillary damage: AGEs and oxidative stress weaken retinal capillaries.
- Blockage & oxygen shortage: Some capillaries get blocked, prompting fragile new vessel growth.
- Vision problems: Fragile vessels bleed; fluid leaks cause macular edema, leading to blurry vision and diabetic retinopathy.
Common theme: kidneys, eyes, and arteries all share microvessels highly vulnerable to high sugar and AGEs.
5. How Medications Help
Metformin (for sugar)
- Reduces glucose production in the liver.
- Helps muscles absorb glucose more efficiently.
- Limitation: Doesn’t stop all glucose from food — dietary spikes still matter, requiring dose adjustments over time.
Statins (for cholesterol)
- Lower LDL cholesterol production in the liver.
- Stabilize plaques and reduce inflammation.
- Limitation: The body may compensate; lifestyle factors still drive LDL, leading to increasing doses over time.
6. Why Dosages Keep Rising
if all above reasons are good, then why dosage has to keep raising. From first principles:
- Ongoing damage: Blood sugar spikes continue damaging vessels, kidneys, and eyes.
- Body adapts: Liver and cells adjust to medication, reducing its relative effect.
- Lifestyle factors: Diet, exercise, and weight strongly influence both sugar and cholesterol levels.
Since body is slowly adapting to medication, it means the same dose produces less effect, it means slow dosage increase is essential
7. Why High Insulin Is a Problem
While insulin is vital, chronically high insulin (hyperinsulinemia) can create new issues:
| System | Effect of Chronic High Insulin |
|---|---|
| Brain | Constant hunger, even when full |
| Heart | Sodium retention → higher BP |
| Liver | Stimulates fat storage, raising triglycerides |
| Circulation | Promotes plaque buildup |
| Metabolism | Suppresses fat burning |
| Long-Term | Pancreas burnout → diabetes onset |
Note: High insulin isn’t the cause of AGEs (that’s glucose), but it worsens metabolic stress, pushing the system toward imbalance.
8. Takeaway: A Holistic Approach
This exploration isn’t medical advice — it’s my personal learning log.
Tracking trends for 15 years has shown me that numbers alone don’t tell the whole story. Understanding the underlying cause-and-effect mechanisms highlights why doctors emphasize:
- Balanced diet and controlled carbs → prevent sugar spikes → reduced insulin production
- Exercise and healthy fats → manage cholesterol naturally.
- Medication as support → metformin and statins help, but don’t replace healthy habits.
High Insulin Resistance → High Sugar → AGEs → damaged vessels → affect multiple organs simultaneously—arteries, kidneys, and eyes—creating a cascade of damage that can lead to strokes, kidney disease, and vision loss.
Addressing the root causes, not just the numbers, is the most effective way to maintain good health.