Summary

Your AGT M235T result determines how much angiotensinogen your liver produces — the raw material for the renin-angiotensin blood pressure system — with GG (T/T) carriers producing ~40% more, making them genuinely salt-sensitive and significantly more responsive to sodium restriction than the general population.

Genotype spectrum

AA (Met/Met — reference)

Your blood pressure system runs on standard fuel supply. Sodium intake affects your BP through the usual mechanisms, but you don't have the genetic amplification that T carriers experience.

AG (Met/Thr — heterozygous)

You have a mild sensitivity signal — enough to benefit from sodium awareness, but not enough to require aggressive intervention. Your moderate angiotensinogen increase means dietary and lifestyle measures are highly effective at keeping things in check.

GG (Thr/Thr — homozygous variant)

Sodium restriction actually works better for you than for most people. This is one of the clearest genotype-to-diet connections in cardiovascular genetics.

Practical takeaway

For GG Carriers (T/T — High Angiotensinogen)

Sodium management (this is your primary lever):
• Target <1,500 mg/day. This is the level where GG carriers show the most significant BP benefit in clinical data.
• Where sodium hides: Processed foods account for ~70% of dietary sodium. Bread, cheese, deli meats, canned soups, sauces, restaurant food. The salt shaker is a minor contributor.
• Practical tracking: Read nutrition labels. A "low sodium" product has <140 mg per serving. Many single restaurant meals exceed your entire daily target.
• Cooking strategy: Cook at home more. Use herbs, spices, citrus, vinegar for flavour instead of salt. If you cook at home 5+ days per week, staying under 1,500 mg is achievable without feeling restricted.
• Eating out: Request no added salt. Choose grilled over processed options. Accept that occasional restaurant meals will exceed your target — consistency over perfection.

Potassium counterbalance:
• Target 3,500-4,700 mg/day from food sources.
• Best sources: sweet potatoes (542 mg each), bananas (422 mg each), spinach (839 mg per cup cooked), white beans (1,189 mg per cup), avocado (485 mg per half), salmon (534 mg per fillet).
• Potassium directly opposes aldosterone-driven sodium retention. For your genotype, this isn't just "healthy eating" — it's targeted biochemistry.

Monitoring:
• Home BP monitor (validated device). Check weekly at the same time, sitting, rested.
• Track trends over weeks, not individual readings. Day-to-day variation is normal.
• Target: consistently below 130/80 mmHg. Ideal: below 120/80 mmHg.
• If trending upward despite dietary intervention, GP consultation for additional measures.

What "working" looks like:
• BP consistently below 130/80 mmHg
• Sodium intake averaging <1,500 mg/day (tracked for a few weeks to establish habits, then intuitive)
• No headaches, visual changes, or other hypertension symptoms
• If previously elevated: BP reduction within 2-4 weeks of consistent sodium restriction

Expected response window: BP response to sodium restriction: 2-4 weeks for measurable change. Full dietary adaptation (taste preferences adjust): 6-8 weeks.
For AG Carriers (Heterozygous)
• Sodium awareness

Evidence detail

What This Gene Does

AGT produces angiotensinogen, the precursor protein that feeds the entire renin-angiotensin system. Renin cleaves angiotensinogen into angiotensin I, which ACE then converts to angiotensin II (the vasoconstrictor). More angiotensinogen means more raw material entering this cascade, which means more angiotensin II production and higher blood pressure drive.

The M235T variant (methionine → threonine at position 235) is linked to higher angiotensinogen levels. This was one of the earliest genetic associations with essential hypertension (Jeunemaitre et al. 1992), and it remains one of the most replicated. The clinical importance isn't just the blood pressure effect — it's the salt sensitivity. GG carriers respond to sodium restriction more than the general population, which makes dietary sodium a genuine precision intervention for this genotype.

Mechanism

Angiotensinogen is the starting point of the renin-angiotensin system:

1. AGT (liver) → angiotensinogen (circulating precursor protein)
2. Renin (kidneys) → cleaves angiotensinogen → angiotensin I
3. ACE → converts angiotensin I → angiotensin II (vasoconstrictor)
4. AGTR1 → angiotensin II receptor → vasoconstriction, aldosterone, sodium retention

The M235T variant increases angiotensinogen production through linkage with a promoter variant (A-6G, rs5051) that increases transcription. More AGT protein → more substrate for renin → more angiotensin I → more angiotensin II → higher blood pressure drive.

Why salt sensitivity matters here:

Angiotensin II stimulates aldosterone release from the adrenal cortex. Aldosterone tells the kidneys to retain sodium and water. When angiotensinogen is constitutively elevated (GG genotype), the system runs at higher baseline aldosterone drive. This means:
• Sodium loading produces a larger BP spike (the system retains MORE of the ingested sodium)
• Sodium restriction produces a larger BP drop (removing sodium removes the substrate that aldosterone was retaining)

This is why GG carriers benefit disproportionately from sodium restriction — they're addressing a specifically amplified pathway, not just following generic advice.

The compound RAS picture:

AGT feeds into ACE feeds into AGTR1. If all three carry high-activity variants (AGT GG + ACE DD + AGTR1 CC), the system is amplified at every step: more substrate, faster conversion, more responsive receptor. This is not additive — it's multiplicative. The blood pressure picture from the complete high-drive RAS is qualitatively different from any single variant.

AGT Angiotensinogen

Summary

Genotype spectrum

Practical takeaway

Evidence detail

Sources (7)