Is coffee really that bad for you?

A very common idea in the wellness and nutrition world is that caffeine (mind you, only from coffee) is not just something bad for you, it is something to be completely avoided. In fact, I often overhear people talking about coffee and caffeine in the same terms they will use for UPF (ultra-processed foods), fried foods or sugary drinks. But is it really that bad to have coffee, and is ditching it the secret to achieving long-term health?

If it is so bad, why is Italy one of the nations in the world with the most people reaching 100 years of age [1]? Certainly, other factors are at play, including a lower intake of ultra-processed foods, but trust me, in Italy it's common to have a few coffees a day every day since early teenage years, and kids are often given coffee-flavoured ice-cream and yoghurt.

When I hear people claiming triumphantly that they have given up caffeine (AKA coffee, but not 90% dark chocolate, which is also a rich source of caffeine) a long time ago, I always ask “Why?”, and the usual answer is: “Because coffee is bad”. When I follow up asking “Do you feel better after eliminating coffee?”, most of the time the answer is “I haven’t felt much difference really”.

So, what is the real deal about caffeine, and why does it have such a bad rep?

Why does coffee have a bad reputation?

The truth is that caffeine can trigger your cortisol response [2], heighten anxiety [3] and overstimulate your nervous system. Some individuals have a genetic variation (technically called SNPs) that makes them more susceptible to caffeine effects [4] as their liver can’t process it as quickly [5].

So, what happens if this is you? Most likely, you will feel nervous after a coffee or not really be drawn to the drink itself. You can do a genetic test to be sure about it, but you will definitely know if caffeine doesn’t agree with you.

What are the potential benefits of drinking coffee?

If you don’t experience palpitations, sweats and increased anxiety when having coffee, there is not necessarily a reason to ditch it, as studies show a moderate intake (200–400 mg/day, AKA max 3 cups of coffee) [6] can:

Reduced all-cause and cardiovascular mortality

Moderate coffee intake (1–3 cups/day) is linked to lower mortality rates, especially in individuals with pre-existing cardiovascular or cerebrovascular disease [7].

Enhanced alertness, attention, and vigilance

Caffeine blocks adenosine receptors, reducing fatigue and improving mental performance [8].

Increased oxygen extraction in the brain

Moderate intake can enhance cerebral oxygen use, potentially boosting cognitive function [9].

Improved glucose tolerance and insulin sensitivity

Caffeine activates ryanodine receptors, enhancing pancreatic insulin secretion and mitigating type 2 diabetes risk [10].

Antioxidant and anti-inflammatory effects

Caffeine can reduce oxidative stress and lipid peroxidation, supporting systemic health [11].

If you don’t experience negative effects from caffeine, there may be no need to avoid coffee. Research suggests that moderate intake is associated with a range of potential health benefits.

This is just an example of nutrition myths, where foods are labelled either “good” or “bad” without a real reason or research backing up certain statements. Always trust healthcare professionals doing their own research and advising you the best foods for your own dietary requirements and genetic makeup, not just following trends.

References

 [1] In 2020, Italy ranked among the top countries for centenarian prevalence, following Japan, France, the United States, and Spain, with 2.3–2.9 centenarians per 10,000 people (Busetta & Bono, 2021) and as of 1 January 2024, Italy had 22,552 centenarians (0.04% of the population) and 844 semi-supercentenarians (≥105 years). (Arosio and Picca, 2024) (Vecchio et al., 2025).

[2] Acute caffeine intake (equivalent to 2–3 cups of coffee) can significantly raise plasma cortisol levels in healthy adults, likely via hypothalamic-pituitary-adrenal (HPA) axis activation. (Raza, Haghipanah and Moradikor, 2024)

[3] High doses (>400 mg/day) can trigger panic attacks in susceptible individuals and increase arousal and avoidance behaviors. (Hoppe et al.,2025) (Meamar et al., 2024).

[4] Many people worldwide carry SNP variants in CYP1A2 that affect coffee metabolism. For rs762551, SNP—that influence caffeine metabolism, the C allele (slow metabolism) is present in roughly 29% of alleles in Latin America, with similar variants common globally. This means that in some populations, about half are fast metabolizers (AA), and the rest are intermediate or slow (AC/CC). Exact global numbers are not available in the provided data, but the variant is widespread across ethnic groups. (İlhan-Esgin and Asil, 2025) (Guevara-Ramírez et al., 2022).

[5] Variants in genes like CYP1A2 can influence caffeine’s pressor and cortisol effects. (Shah et al., 2023)

[6] (Kannen and Garcia, 2025)

[7] (Kannen and Garcia, 2025) (Mattioli, 2025)

[8] (Rosen et al., 2023) (Mattioli, 2025)

[9] (Bagheri Davisaraei et al., 2024)

[10] (Baite, Mandal and Purkait, 2024)

[11] (Barcelos et al., 2020)