Short answer: Occasionally is fine for most healthy adults, but drinking a sweet Red Bull every day is not recommended — mainly because of the caffeine (80 mg per 8.4 fl oz can) and the high added sugar (≈26–27 g per can). Over time daily intake can raise your risk of sleep problems, higher calorie/sugar intake, and could contribute to heart or blood‑pressure issues in people with sensitivity or underlying conditions. (redbull.com)

Why (the important facts)

• Caffeine per can: a standard 8.4 fl oz (250 ml) Red Bull has about 80 mg of caffeine. That’s roughly the same as a small cup of coffee. (redbull.com)
• Safe caffeine limits: most health authorities say up to ~400 mg/day for healthy adults is unlikely to cause harm; pregnant people are generally advised to keep caffeine ≤200 mg/day. If you drink multiple caffeinated products, the totals add up quickly. (fda.gov)
• Sugar and calories: a regular can contains ~26–27 g added sugar and ≈110 kcal. Regular daily sugary drinks are linked to higher risk of weight gain, type 2 diabetes and cardiovascular disease. The American Heart Association recommends limiting added sugar (about ≤25 g/day for most women, ≤38 g/day for most men). (harristeeter.com)
• Other risks: energy drinks have been associated with sleep disturbance, anxiety, palpitations and, in susceptible people, abnormal heart rhythms and elevated blood pressure — risks increase with higher intake, mixing with alcohol, exercise, certain medicines, or preexisting heart conditions. Adolescents and children are generally advised to avoid energy drinks. (theguardian.com)

What “safe” daily use would look like (practical)

• If you want a daily pick‑me‑up, one 8.4‑oz can (80 mg caffeine) usually keeps you well under the 400 mg/day adult guideline — but watch other sources (coffee, tea, soda, meds). (redbull.com)
• Prefer sugar‑free options (Red Bull Sugarfree/Zero) if your main concern is added sugar/calories — but they still contain caffeine and some artificial sweeteners; long‑term effects of frequent artificial sweetener use are still being studied. (harristeeter.com)
• Avoid daily consumption if you are pregnant, breastfeeding, under 18, have high blood pressure, heart disease, anxiety disorders, or take medications that interact with caffeine. Stick to the lower pregnancy limit (≈200 mg/day) if pregnant. (efsa.europa.eu)
• Don’t mix energy drinks with alcohol or use them to mask intoxication — that combination increases risk of injury and cardiac events. (efsa.europa.eu)

Bottom line

• One can of Red Bull occasionally is fine for most healthy adults.
• Daily drinking of the sugar‑sweetened product is not ideal because of added sugar and potential metabolic/heart risks; if you do choose daily use, consider a sugar‑free version and keep total daily caffeine below recommended limits. If you have medical conditions (or are pregnant, under 18, or on certain medications), avoid daily energy drinks and check with your clinician.

If you want, I can:

• Compare a regular Red Bull vs Sugarfree/Zero in calories, sugar and caffeine; or
• Help you estimate your total daily caffeine from all sources if you tell me what else you typically drink.