Most shoppers check dates on food, drinks and medicine, but Executive Digest reports that many other household items also carry limited lifespans. In an article published on 11 October 2026, the Portuguese outlet lists ten products that people often keep long past their recommended use-by point, including mascara, moisturiser, insect repellent, batteries, motor oil, toothpaste, tea bags, bleach, carbon monoxide detectors and hand sanitiser.
The guidance draws on advice from Which?, the consumer advocacy organisation, which recommends checking packaging first and following any expiry date or instruction supplied by the manufacturer. Executive Digest notes that when packaging has been discarded or carries no clear date, general rules of thumb can help users decide when an item should be replaced.
Why it matters
Some products simply lose effectiveness over time, while others can become a health or safety risk once used beyond the recommended window, according to Executive Digest. The distinction matters because the consequences differ: a weakened insect repellent may lead to more bites, whereas a degraded cosmetic can harbour bacteria that end up applied directly to the skin or eyes.
Which? senior researcher Sara Spary told the organisation that mascara has a particularly short life, typically lasting between three and six months. The reason lies in the product itself. Because mascara is a liquid, Executive Digest reports, it can create conditions in which bacteria multiply, and those bacteria are then transferred to the lashes and the eye area.
Packaging usually signals the recommended window through a symbol of an open container paired with a number. A "3M" marking means three months and "6M" means six months after opening. Once that period passes, Which? advises replacing the mascara rather than continuing to use it.
Repellent, batteries and skincare
Insect repellent also has a finite shelf life. Matt Stevens, a principal researcher at Which?, said such products last roughly three years. Executive Digest reports that while active ingredients used to ward off insects, such as DEET and picaridin, are relatively stable and hold up for a long time, other components in the sprays can break down faster.
Storage conditions affect how well a repellent keeps. Which? recommends keeping it somewhere cool, dry and dark to extend its usable life. A repellent older than three years has not necessarily stopped working altogether, but its effectiveness may decline, and replacing it is described as the safer option once the recommended period has passed.
Batteries last considerably longer, though they are not indefinite either. Depending on type and manufacturer, Executive Digest reports a lifespan of between 10 and 15 years. Callum Pears, a senior researcher at Which?, said manufacturers typically print both a production date and an expiry date on the packaging. Duracell Plus AA and AAA alkaline batteries, for example, carry a ten-year expiry.
For anyone stockpiling batteries for emergencies, Pears recommends disposable lithium cells over alkaline ones. According to Executive Digest, lithium batteries can be stored reliably for more than 15 years and carry a much lower risk of leaking chemicals.
Skincare products are subject to their own limits, particularly once opened. Which? says moisturiser should be replaced about six months after opening. James Aitchison, a senior researcher at the organisation, explained that cosmetic products normally carry either an expiry date or the PAO symbol, which stands for "Period After Opening". The symbol shows an open container with a number and indicates how long the product remains safe and effective once unsealed.
After that point, active ingredients can lose potency and the product may stop delivering the expected result. In a worse case, Executive Digest reports, preservatives can break down and allow bacteria and fungi to grow. Exposure to those microorganisms can cause skin irritation, rashes and infections. The risk is described as especially relevant for products sold in jars, since cream is often scooped out with fingers.
Motor oil and the wider list
Motor oil also has a use-by window. Which? puts its lifespan at between two and five years. One way to judge the condition of oil is by colour: fresh oil tends to look golden or amber, while older oil turns dark brown. Dino Buratti, a senior researcher at Which?, warned that oil degrades over time and that using degraded oil can cause serious engine problems.
Executive Digest's list also includes toothpaste, tea bags, bleach, carbon monoxide detectors and hand sanitiser among the items that should not be kept indefinitely. The article does not give individual timelines for each of those products beyond noting that they belong in the same category of goods with limited useful lives.
The broader point from Which?, as relayed by Executive Digest, is that packaging should be the first reference point. Where a date or manufacturer instruction is missing, general guidance can serve as a fallback, but the organisation's researchers consistently point to replacement once the recommended period has elapsed.
For consumers, the practical step is to check the open-container symbols and printed dates on items already in bathrooms, garages and cupboards, and to treat the ten products named as perishable rather than permanent.
