Coffee remains one of the most popular drinks in Ukraine, but dietitian Yevheniya Rozum has advised that healthy adults should limit their intake to a maximum of 400 milligrams of caffeine a day.
The limit equates to roughly three or four espresso shots. Rozum said a single espresso contains about 100 milligrams of caffeine, though the exact amount varies depending on the coffee bean variety and its processing.
She advised people to track their total caffeine intake rather than counting cups, adding that those who struggle to sleep or have high blood pressure should reduce their consumption to one or two cups a day if their body tolerates it.
Rozum strongly advised against giving coffee to teenagers. She said caffeine affects adenosine receptors and can damage the sleep, nervous and cardiovascular systems of a developing body.
Rozum is a doctor with more than 30 years of medical experience, including nine years as a dietitian, who trained at the Bogomolets National Medical University and the Shupyk National Healthcare University of Ukraine.
Caffeine sensitivity and sleep
The effect of heavy coffee consumption depends on genetics and individual sensitivity. Rozum said some people tolerate caffeine well and feel a pleasant cheerfulness, while sensitive individuals may experience anxiety, strong heartbeats, hand tremors or headaches.
Even those who comfortably drink five or six cups a day face health risks, including habituation. Rozum said caffeine provides energy on loan by blocking adenosine receptors, which temporarily reduces feelings of sleepiness and masks fatigue. She warned this can leave people exhausted without understanding why they feel tired.
Research shows that drinking coffee in the afternoon reduces the deep sleep phase needed for the body to recover, leading to poor sleep quality and grogginess the next day.
Caffeine takes between 14 and 16 hours to clear the body completely. Rozum said a coffee consumed after 4 p.m. will leave half its dose in the system seven to eight hours later, disrupting sleep.
Timing and meals
The dietitian said coffee should be drunk in the first half of the day, but never on an empty stomach immediately after waking up.
Cortisol, a stress hormone, peaks in the morning to help the body transition from sleep to an active state, before gradually decreasing after breakfast. Rozum said drinking coffee on an empty stomach can increase cortisol or keep it elevated in the blood for longer.
She noted that Ukrainians already live under background stress, making it inappropriate to artificially sustain high stress hormone levels.
Instead, Rozum recommended eating breakfast first and waiting until natural cortisol drops before drinking coffee between 10 a.m. and 11 a.m. to provide a small stimulating boost. A second cup can be drunk after lunch, between 2 p.m. and 3 p.m.
People who experience tremors and anxiety should drink only decaffeinated coffee. Rozum said caffeinated coffee is also strictly prohibited for patients with certain neurological and psychoneurological conditions, or those experiencing a hypertensive crisis.
Patients whose blood pressure has stabilised following medical treatment can resume drinking coffee in measured amounts, provided they have their doctor's permission, she said.
