Woman dies from a caffeine overdose—what is the recommended safe daily limit for adults?

The tragic death of 32-year-old Melbourne woman Christina Lackmann, who died after taking a suspected overdose of caffeine tablets, has brought renewed attention to the question: how much caffeine is actually safe? Caffeine, when consumed in concentrated forms, can have fatal consequences.According to the Daily Mail, Ms. Lackmann had called for emergency help after feeling dizzy and numb, but her case was misclassified as non-urgent. Despite 14 callback attempts by emergency services, help arrived over seven hours later.A toxicology report revealed she had consumed a lethal dose of caffeine, though the exact quantity remains unclear. Experts believe her death could have been prevented with timely medical intervention.But how much caffeine is too much? And how can we make sure we stay within safe limits?

How much caffeine is safe?

The U.S. Food and Drug Administration (FDA) states that up to 400 milligrams of caffeine per day is generally safe for most healthy adults. This might include: 4–5 cups of regular brewed coffee, 10 cans of cola, and 2 energy drinks. However these guidelines are not for everyone. Factors like body weight, health conditions, medications, and individual sensitivity can change how your body reacts to caffeine.

When caffeine becomes dangerous

Though 400 mg is considered safe, caffeine toxicity can occur at much higher levels. According to the FDA, toxic effects such as seizures can happen with a rapid intake of around 1,200 milligrams of caffeine — the amount in less than half a teaspoon of pure caffeine powder.

However, experts also explain that these toxic amounts are rarely achieved through coffee alone. Instead, overdoses are more often linked to caffeine tablets, powders, or highly concentrated supplements.

In Lackmann’s case, the caffeine levels found in her body could not have come from drinking coffee alone, and an email on her phone revealed that she had ordered caffeine tablets the same day she died.

Where caffeine might be hiding

Here are the products that might contain caffeine that you need to be on a lookout for: Energy bars and drinksProtein powdersChewing gumIce creamOver-the-counter medicationsSome of these products have added caffeine that may not be clearly labeled.

While the FDA requires caffeine to be listed in the ingredients when it’s added as a standalone substance, it does not mandate the exact amount to be stated on food labels. And when caffeine is naturally occurring (as in chocolate), it may not be flagged clearly at all.That means it’s up to you to stay alert — especially when trying a new food or supplement.

Warning signs of too much caffeine

Consuming more caffeine than your body can handle may lead to uncomfortable — or dangerous — symptoms.

These symptoms include: rapid heartbeat, palpitations, anxiety or jitteriness, high blood pressure, nausea or upset stomach, insomnia, and headaches. Moreover in extreme cases, caffeine overdose can also lead to vomiting, confusion, convulsions, or even death.

Tips to stay safe with caffeine

Know your sources: Look beyond your coffee mug. Track energy drinks, soft drinks, chocolate, and supplements.Read labels carefully: Look for caffeine listed in the ingredients. If it's not clear, ask the retailer or manufacturer.Be cautious with new products: Especially ones marketed as energy boosters or workout enhancers.Avoid highly concentrated forms: Pure caffeine powder or tablets can be extremely dangerous, even in small quantities.