McDonald's McCafé Brewed Coffee (Medium)に含まれるカフェイン量はどれくらい？

A medium McDonald's McCafé Brewed Coffee (473 ml / 16 fl oz) contains 145 mg of caffeine. That figure places it squarely in the moderate range for a brewed coffee of this size — it delivers roughly 30.7 mg of caffeine per 100 ml, which is slightly higher than the 40 mg per 100 ml typical of a standard home-brewed drip coffee (96 mg in 240 ml) but well below many specialty-coffee shop equivalents. In practical terms, the 145 mg dose is equivalent to about 1.5 standard cups of drip coffee, making it a familiar benchmark for anyone who tracks their daily intake.

Caffeine from a liquid like brewed coffee is absorbed rapidly through the small intestine, with peak plasma concentrations typically reached between 30 and 60 minutes after consumption. For most healthy adults, a 145 mg dose produces a noticeable but not overwhelming lift: increased alertness, improved concentration, and a mild reduction in perceived fatigue. Because this is a straightforward filtered coffee without added sugars or fats, the caffeine effect arrives without the metabolic distraction of a high-calorie load, so the subjective onset is often reported as clean and swift. The intensity and duration of that effect, however, depend on individual factors — body mass, habitual tolerance, liver enzyme activity (particularly CYP1A2), and whether the coffee is consumed with food. On an empty stomach, the same 145 mg can feel significantly more stimulating than it does after a meal.

McDonald's McCafé Brewed Coffee (Medium)が体内にどれくらい残るか

Caffeine follows first-order elimination kinetics in the body, with a population-average half-life of 5.7 hours. That means after 5.7 hours, half of the original dose remains pharmacologically active; after another 5.7 hours, half of that remainder is left, and so on. For a 145 mg dose from a medium McCafé Brewed Coffee, the arithmetic works out as: remaining caffeine = 145 × 0.5^{(hours / 5.7)}. At 3 hours post-consumption, the residual is approximately 101 mg; at 6 hours, 70 mg; at 9 hours, 49 mg; and at 12 hours, 34 mg. These numbers are not trivial — even at the 9-hour mark, the remaining 49 mg is roughly equivalent to half a cup of standard drip coffee, enough to sustain measurable adenosine-receptor blockade in sensitive individuals.

If someone drinks a medium McCafé at 15:00 (3 p.m.), the timeline becomes concrete. By 18:00, about 101 mg remains — still a substantial stimulant load during the late afternoon. By 21:00, the residual is roughly 70 mg, which is more caffeine than a single espresso shot (63 mg). At midnight, 34 mg lingers, comparable to a can of Coke Zero. For a person aiming for a 23:00 bedtime with minimal sleep disruption, that midnight residual can be problematic. Research by Drake et al. (2013) demonstrated that 400 mg of caffeine taken six hours before bed still reduced total sleep time by over an hour, and even lower doses can fragment sleep architecture. The caffeine half-life calculator lets you model this decay precisely for your own consumption time and sensitivity profile.

With a 145 mg dose, an adult can consume up to two medium McCafé Brewed Coffees in a day and remain under the FDA's 400 mg daily guidance for healthy adults (2 × 145 = 290 mg). A third cup would push the total to 435 mg, exceeding the limit by 35 mg. The European Food Safety Authority (EFSA) sets the same 400 mg ceiling for adults and additionally recommends that single doses not exceed 200 mg — a threshold that the McCafé's 145 mg comfortably respects. For pregnant individuals, the EFSA advises limiting daily intake to 200 mg, meaning one medium McCafé (145 mg) leaves only 55 mg of headroom for any other caffeine source that day. Adolescents should limit caffeine to no more than 2.5 mg per kilogram of body weight per day; for a 50 kg teenager, that's 125 mg, so a full medium McCafé would already exceed the safe daily cap.

Sleep timing is a critical consideration. Using the 5.7-hour half-life, if someone wants no more than 50 mg of caffeine remaining in their system at a 23:00 bedtime, they need to work backward. The equation: 145 × 0.5^(t/5.7) = 50, solving for t gives t = 5.7 × log₂(145/50) ≈ 5.7 × 1.53 ≈ 8.7 hours. That means the last cup should be consumed no later than about 14:20 (2:20 p.m.). For a more conservative threshold of 25 mg at bedtime, the cutoff moves earlier to around 11:40 a.m. These calculations align with the sleep-disruption findings of Drake et al. (2013), which showed that even moderate caffeine doses taken in the afternoon can impair sleep quality. The latest cup before bedtime tool automates this math for any dose and bedtime, while the safe daily limit by body weight tool personalizes the ceiling based on individual characteristics.

Among major coffee-shop brewed coffees of similar volume, the medium McCafé's 145 mg is on the lower end. A Grande (473 ml) Starbucks Pike Place Brewed delivers 310 mg — more than double the McCafé dose — while a medium Dunkin' Original Blend (414 ml) contains 210 mg. Even accounting for the slightly smaller Dunkin' serving, the concentration difference is stark: Dunkin' packs about 50.7 mg per 100 ml versus McCafé's 30.7 mg. This places McDonald's brewed coffee closer to the caffeine density of a typical home brew than to the high-octane profiles of its competitors. The side-by-side drink comparison tool allows direct head-to-head visualization of these numbers.

When compared with espresso-based drinks of equal volume, the McCafé brewed coffee holds its own as a moderate source. A Grande Starbucks Caffè Latte (150 mg), Cappuccino (150 mg), and Caramel Macchiato (150 mg) all contain roughly the same caffeine as the McCafé, because those drinks are built on a single shot of espresso (63 mg) plus milk, with the larger sizes adding a second shot only in some recipes. A Grande Flat White (195 mg) and Caffè Mocha (175 mg) edge slightly higher. The McCafé's 145 mg is also comparable to a 473 ml can of Monster Energy (160 mg) and significantly more than a 250 ml Red Bull (80 mg) or a 355 ml Coke Zero (34 mg). In the broader landscape of caffeinated beverages, the medium McCafé Brewed Coffee is a middle-of-the-road choice — stronger than tea or soda, but far less intense than the 300 mg-plus giants of the coffee world.

McDonald's McCafé Brewed Coffee (Medium)の数値を左右する要素

The 145 mg figure represents McDonald's standard medium brewed coffee as served from their automated drip machines in most markets. However, the actual caffeine content of any single cup can wander around that number due to several variables. First, serving size: a small McCafé Brewed Coffee (typically 12 fl oz / 355 ml) will contain proportionally less caffeine — roughly 109 mg if the concentration holds constant — while a large (20–22 fl oz) can push beyond 200 mg. McDonald's does not publish a detailed caffeine-by-size chart for all regions, but the concentration per ounce tends to be consistent because the brew ratio is machine-controlled.

Second, the coffee blend and roast profile matter. McDonald's uses a proprietary blend of 100% Arabica beans, which naturally contain less caffeine than Robusta beans. Arabica beans typically range from 0.8% to 1.4% caffeine by weight, whereas Robusta can reach 2.2% or higher. Within the Arabica category, lighter roasts retain slightly more caffeine per bean than darker roasts, though the difference by volume is minimal because darker beans expand and lose density. McDonald's roast is a medium-dark profile, so the 145 mg value sits comfortably within the expected range for a 16 oz Arabica brew. Third, batch-to-batch variation in commercial drip machines — water temperature, contact time, and grind size — can shift extraction efficiency by a few percent. In practice, the caffeine content of a medium McCafé likely falls between 130 mg and 160 mg, with 145 mg as the central estimate.

For those seeking a lower-caffeine option, McDonald's offers decaffeinated brewed coffee. Decaf is not caffeine-free; the decaffeination process typically removes 97% or more of the original caffeine, leaving a residual of about 2–5 mg per 16 oz serving. That makes it a viable choice for late-day consumption or for individuals who are limiting their intake. The decaf version uses the same Arabica blend, so the flavor profile remains similar, though some aromatic volatiles are inevitably lost during processing.

• Serving size: Small (~12 oz) ≈ 109 mg; medium (16 oz) = 145 mg; large (20–22 oz) ≈ 180–200 mg.
• Brew method: McDonald's uses automated drip with controlled water temperature and pre-measured grounds, yielding consistent extraction.
• Bean origin: 100% Arabica beans from multiple origins, blended for consistency; seasonal shifts in crop composition may cause minor caffeine fluctuations.
• Decaf version: Contains less than 5 mg per 16 oz serving, suitable for caffeine-restricted diets.

この数値の出典

The 145 mg value for a medium McDonald's McCafé Brewed Coffee is drawn from McDonald's own published nutritional information, which is periodically updated on their corporate websites and in-store materials. This figure aligns closely with independent laboratory analyses and entries in the USDA FoodData Central database, though slight discrepancies exist across sources. For example, some third-party databases report 140 mg or 150 mg for the same serving size, reflecting batch-to-batch variability and differences in testing methodology. We treat the manufacturer's figure as the primary reference because it represents the target formulation, but we acknowledge that any single cup may deviate by ±10% in practice. Our dataset page (the open caffeine dataset behind these pages) documents the provenance, date of last verification, and any conflicting values we have encountered.

Published caffeine figures for the same drink can disagree for several reasons: the specific blend of beans used at the time of testing, the calibration of brewing equipment, the analytical method (HPLC vs. UV spectrophotometry), and even the roast batch. We monitor official updates and credible third-party sources, and we will revise the 145 mg figure if new, reproducible evidence demonstrates a systematic shift. This transparency is why the page includes the decay model, the comparison set, and the explicit daily-guidance share — so that even if the absolute number shifts by a few milligrams, the context and the tools remain useful.

結論

A medium McDonald's McCafé Brewed Coffee (473 ml) contains 145 mg of caffeine, which is about 1.5 times the caffeine in a standard 240 ml cup of drip coffee (96 mg) and represents 36% of the FDA's 400 mg daily guidance for healthy adults. The dose decays with a half-life of 5.7 hours, leaving roughly 101 mg after 3 hours, 70 mg after 6 hours, and 34 mg after 12 hours. For most people, one or two of these coffees per day fit within safe limits, but timing matters: to keep bedtime caffeine below 50 mg for an 23:00 sleep, the last cup should be finished before about 14:20. Compared to other coffee-shop brews of the same size, the McCafé is moderate — less than half the caffeine of a Starbucks Pike Place (310 mg) and lower than a Dunkin' Original Blend (210 mg). The figure comes from McDonald's published data and is cross-checked against independent databases, with the understanding that real-world cups may vary by ±10%.