Hi. I've got hypertension but I like drinking lager...

The short version: alcohol raises blood pressure in a dose-dependent way, and for someone with hypertension, even moderate regular drinking works against control.

The evidence here is consistent and comes from several designs. A randomized crossover trial from 1985 gave 46 normotensive men low-alcohol beer and found systolic pressure dropped by about 4 mmHg, and when they resumed normal drinking, blood pressure rose back within two weeks [1]. That is a direct causal test, not an association. A 1994 study in 14 hypertensive men who drank daily showed a biphasic pattern: alcohol lowered pressure for a few hours after drinking, then raised it in the early morning, so a casual daytime reading could miss the real burden [3]. A Mendelian randomization study from 2015 using the ALDH2 gene variant in over 7,000 South Koreans confirmed that alcohol causally raises blood pressure and worsens other cardiovascular risk factors [2]. That design is important because it is not vulnerable to the usual confounders that plague observational studies.

The 2025 lifestyle guideline review from ESC and AHA/ACC both recommend limiting alcohol for hypertension, and the Korean and Taiwanese guidelines do the same [8]. The Korean population study from 2004 found that light drinking (1-15 g/day) was associated with lower metabolic syndrome risk, but heavy drinking (30+ g/day) clearly raised blood pressure and triglycerides [5]. That J-shaped curve is common in the literature, but the protective effect of light drinking is almost certainly confounded by healthier lifestyle in light drinkers compared to non-drinkers (who include former heavy drinkers who quit for health reasons). The Mendelian randomization study, which is not vulnerable to that bias, found no protective effect at any level [2].

For a person with hypertension, the practical question is what level of drinking is compatible with good control. The evidence does not support a safe threshold. The 1985 trial found a dose-response: each 100 ml of alcohol per week (roughly one standard drink) raised systolic pressure by about 1 mmHg, independent of weight [1]. A hypertensive patient drinking three lagers a night (about 6-8 standard drinks) would be adding 6-8 mmHg to their systolic pressure from alcohol alone, on top of whatever medication is doing. The 1992 trial of advice to reduce drinking in hypertensive heavy drinkers found that cutting from about 60 units/week to 30 units/week lowered standing diastolic pressure by about 5 mmHg [4].

The mechanism is straightforward: alcohol activates the sympathetic nervous system, raises heart rate, and constricts blood vessels [6, 7]. It also disrupts the colloidal stability of blood by dehydrating and altering electrolyte balance, which worsens blood sludging and increases vascular resistance. For someone with hypertension, whose vascular system is already under pressure, adding a sympathetic stimulant is working against every antihypertensive drug and lifestyle measure.

My call: for hypertension, the safest amount of alcohol is none. If you drink, the evidence shows that even moderate regular intake measurably raises blood pressure, and the effect is dose-dependent. Confidence: high.