Is It Better to Drink From a Straw or a Cup?

Neither option is universally better. Drinking from a straw can protect your teeth from acidic beverages and help some people with swallowing problems, but it also introduces concerns you would never face with a plain cup, from swallowing extra air to the chemicals lurking in certain straw materials. The real answer depends on what you are trying to optimize, and the trade-offs are more interesting than you might expect.

Straws and Your Teeth

The strongest case for straw drinking is dental. When you sip an acidic drink from a cup, the liquid washes over your front teeth and pools around your molars. A straw, especially one positioned toward the back of your mouth, can bypass much of that contact. A videofluoroscopic study found that most participants avoided fluid contact with both their front teeth and their molars when using a straw, and the time that liquid spent touching the front teeth dropped significantly compared to cup drinking.¹ The researchers tested both narrow and wide straws and found the benefit held across types, though positioning mattered. When the straw sat farther back in the mouth, the reduction in tooth contact was more pronounced.

This matters most for drinks that are acidic or sugary, like soda, citrus juice, sports drinks, or sweetened iced tea. If you are mostly drinking water, the erosion question is irrelevant, and the straw offers no dental advantage. For people who drink several acidic beverages a day, though, a straw is one of the simpler things you can do to reduce the cumulative exposure your enamel takes. The catch is that you actually have to keep the straw behind your front teeth for this to work. If you sip with the tip resting right against your upper incisors, you are bathing those teeth in exactly the liquid you were trying to divert.

How Much Liquid You Get Per Sip

Cups deliver more liquid per sip than straws do, and the difference is not subtle. Research measuring sip volumes found that cup drinking produced larger sips than straw drinking in adults, with a reasonable average around 25 milliliters per sip for men and 20 milliliters for women when drinking from a cup.² Straw sips were consistently smaller. Interestingly, the difference faded in older adults, whose sip volumes were smaller regardless of the vessel.

A separate study of elderly participants confirmed this pattern from a different angle. Cup drinking took less total time to consume a given volume of liquid, and the final amount consumed was larger with the cup.³ The flip side is that the cup also produced more oral spillage. So while cups are faster and more efficient at getting liquid in, they are messier, and the speed itself is not always desirable. If you are trying to stay hydrated and tend to neglect your water bottle, a cup will generally get you there faster. If you are managing intake carefully, a straw gives you more natural portion control per sip.

Swallowing Problems and the Straw Question

For people who have trouble swallowing, the straw-versus-cup question stops being a preference and starts being a clinical one. Speech-language pathologists and rehabilitation specialists have studied this in detail, and the findings are more nuanced than you might guess.

In a study of post-stroke patients assessed with videofluoroscopy, the overall scores measuring aspiration risk did not differ significantly between straw and cup drinking. But when researchers looked only at patients who had aspiration trouble with both methods, the straw produced better swallowing function scores than the cup. The authors noted that “advantages of the straw over the cup were clear” in that subgroup, but they also found that some patients aspirated only with the straw and not the cup.⁴ In other words, the straw helped certain patients and hurt others. There was no blanket recommendation.

A similar pattern emerged in a study of patients with symptoms of oropharyngeal dysphagia, where aspiration scores were compared across different volumes of liquid. At every volume tested, the scores were close to baseline for both straw and cup, and none of the differences reached statistical significance.⁵ For most people with swallowing difficulty, neither utensil is dramatically safer across the board.

One area where straws do change the mechanics meaningfully involves airway closure during sequential swallowing. When you drink continuously through a straw rather than taking discrete sips, your throat tends to maintain more sustained airway protection. A study of healthy adults found that straw drinking was significantly more likely to produce sequential swallows with greater sustained airway closure compared to cup drinking.⁶ That sounds protective, but the clinical significance for patients with swallowing disorders is still being worked out. The takeaway for anyone managing dysphagia is that the choice of utensil should be guided by their specific swallowing pattern, ideally assessed by a professional, not by a blanket rule.

Bolus Control in Older Adults

Even for elderly people without a diagnosed swallowing disorder, straws may help with one specific problem: keeping liquid from escaping the mouth during swallowing. The study of elderly sequential swallowing found that while the cup allowed faster intake, the straw gave better containment of the liquid within the oral cavity.³ Spillage was notably higher during cup drinking. Neither method caused aspiration in the study participants, so the risk difference was cosmetic and functional rather than medical. But for an older person who finds liquids escaping from the sides of their mouth while drinking from a cup, a straw can make meals less frustrating and less messy.

Gas, Bloating, and Air Swallowing

One of the most commonly repeated claims about straws is that they make you swallow more air, leading to bloating and gas. The mechanism is straightforward: when you suck on a straw, you draw air into your mouth along with the liquid, and some of that air gets swallowed. This is aerophagia, and it can cause belching, a feeling of fullness, and intestinal gas.

How much this actually bothers you depends on how sensitive your gut is. If you have irritable bowel syndrome or tend toward bloating after meals, straws can make things worse. If your digestion is uneventful, you probably will not notice the extra air at all. There is no research showing that straw drinking causes serious gastrointestinal problems in healthy people, but for anyone who already deals with uncomfortable bloating, switching to a cup for carbonated or gas-producing beverages is a simple experiment worth trying.

Carbonation amplifies the issue. Sipping sparkling water through a straw combines the air you are pulling in with the carbon dioxide already dissolved in the drink. A cup lets you take a sip with less negative pressure and less incidental air intake. If bloating is your main concern, the cup wins for fizzy drinks.

The Wrinkle Concern

Dermatologists and skincare forums have long warned that repeated straw use can contribute to fine lines around the mouth, sometimes called “smoker’s lines” or perioral wrinkles. The logic tracks: pursing your lips around a straw recruits the orbicularis oris muscle in a repetitive motion, and over years, that repeated contraction could accelerate the breakdown of collagen in the skin around the lips.

There is no controlled trial proving that straw drinking causes wrinkles. The concern is based on the same mechanical principle behind expression lines elsewhere on the face, where repetitive muscle contraction in the same pattern eventually creases the overlying skin. Whether this adds up to a visible difference depends on genetics, sun exposure, skin type, and how many years of daily straw use you are talking about. For most people drinking through a straw a few times a day, the effect is likely negligible compared to sun damage and aging. But if you are already investing heavily in anti-aging skincare and want to minimize every controllable variable, cup drinking eliminates this particular repetitive motion entirely.

Safety Risks with Rigid Straws

The rise of reusable straws, especially metal and glass varieties, has introduced a category of injury that did not exist when most straws were flimsy plastic tubes. A study of straw-related emergency department visits found that injuries most commonly affected the mouth, eyes, and internal structures, with poking injuries accounting for over half of all cases.⁷ The majority of these injuries occurred in children aged three and younger, and reusable straw materials were associated with significantly more lacerations and oral injuries than disposable ones.

Some of the case reports are alarming. A four-year-old boy suffered a penetrating internal carotid artery injury after falling with a metal straw in his mouth, resulting in hemorrhagic shock and reduced blood flow to one side of the brain.⁸ This is a rare but catastrophic outcome. A disposable plastic or paper straw would buckle or bend on impact. A metal straw does not.

For adults, the risk is low. You are unlikely to fall onto your own straw. But for households with toddlers, the shift to rigid reusable straws deserves some thought. Silicone straws offer the reusability benefit without the rigidity, and silicone tips that fit over metal straws exist for the same reason. If your child walks around with a cup, a flexible straw is simply a safer choice.

What Is Actually in Your Straw

The push to replace single-use plastic straws led to a boom in paper and plant-based alternatives, but these replacements carry a chemical wrinkle that most consumers do not know about. An analysis of 43 brands of straws found that while the plastic straws tested contained no measurable PFAS (the group of persistent synthetic chemicals often called “forever chemicals”), paper and plant-based straws contained up to 21 different PFAS compounds.⁹ The concentrations varied widely between brands, with total PFAS levels ranging from trace amounts to roughly 29 nanograms per straw. The most commonly detected compounds included PFBA, PFOA, and PFHxA.

The researchers also tested whether those chemicals leach into the liquid you are drinking. In the brand with the highest PFAS levels, about two-thirds of the total extractable PFAS migrated into the water, and warmer temperatures increased the leaching.⁹ This does not mean every paper straw is a health hazard. The amounts involved are tiny, and for occasional use, the exposure is likely negligible. But the irony is hard to miss: the “eco-friendly” straw you chose specifically to avoid plastic may contain chemicals that the plastic version did not. Stainless steel and glass straws avoid this problem entirely, as do silicone straws, though silicone has not been studied as thoroughly for chemical leaching.

Environmental Trade-Offs Are Not Simple

Switching from plastic to paper or plant-based straws is often framed as a clear environmental win. The marine pollution argument is real, since plastic straws are among the most common items found in ocean cleanups and inside marine animals. But a life cycle assessment of disposable straw types in the United States found that the environmental picture is more complicated than the ocean narrative suggests.

The analysis estimated that the roughly 500 million straws consumed daily in the US carry significant environmental burdens regardless of material. Plant-based alternatives like PLA (a corn-derived bioplastic) and paper actually scored worse than polypropylene plastic on a composite environmental index that accounts for energy use, emissions, water consumption, and other impacts across the full life cycle.¹⁰ The feedstock manufacturing stage, where the raw materials are grown and processed, drove most of the environmental burden. Increasing the marine litter rate in the model did not change the relative ranking much. Replacing plastic straws with plant-based ones reduces ocean plastic but trades that benefit for higher impacts in categories like land use, water use, and greenhouse gas emissions.

This does not mean you should go back to plastic straws. It means the decision involves trade-offs rather than a clean win. If marine pollution is your top priority, paper and PLA straws are better. If your primary concern is total carbon footprint, a reusable straw you actually wash and reuse hundreds of times is the only option that meaningfully reduces your per-drink impact. And if you can simply drink from the cup, you avoid the entire straw supply chain altogether.

When Each Option Actually Makes Sense

Practical advice depends on what you are drinking and why. For acidic drinks like juice, soda, wine, or kombucha, a straw positioned behind the front teeth reduces enamel exposure and is worth the minor inconvenience. For water, there is no dental reason to bother with a straw. For carbonated drinks, especially if you are prone to bloating, a cup will minimize the air you swallow. For hot drinks, a cup is standard for good reason; drawing near-boiling liquid through a straw puts it in direct contact with your soft palate before you can gauge the temperature, and the straw itself may leach chemicals more readily at higher temperatures.

If you have a swallowing disorder, neither a straw nor a cup is universally safer. Your specific swallowing pattern determines which is less risky, and a clinician can test both during a swallowing evaluation. If you are caring for a toddler, flexible straws are safer than rigid ones, and open cup practice is a normal part of oral motor development that you do not want to skip entirely. If you are choosing reusable straws for environmental reasons, steel or glass straws avoid the PFAS concern associated with paper alternatives, but keep them away from small children who might fall while using them.

For most healthy adults drinking non-acidic beverages, the honest answer is that it does not matter much. The differences in sip volume, air intake, and swallowing mechanics are real but small in practical terms. The scenarios where the choice matters most are the ones with a specific concern attached: protecting enamel, managing dysphagia, avoiding chemical exposure, or keeping a toddler safe.

Straw Hygiene and Reusable Straw Maintenance

Reusable straws need to be cleaned after every use, and most people underestimate how quickly the inside of a narrow tube becomes a hospitable environment for bacteria and mold. The warm, moist, nutrient-rich interior of a straw that held juice or a smoothie is an ideal growth medium. Most reusable straws come with a thin brush designed to scrub the interior, and actually using it matters. Rinsing alone does not reach the biofilm that can form on the inner walls.

Silicone straws are the easiest to clean because they can be boiled, run through the dishwasher, and even turned inside out for inspection. Metal straws are dishwasher-safe but opaque, so you cannot see whether residue remains inside. Glass straws let you see the interior but are fragile. Bamboo straws are the hardest to clean thoroughly because the porous material absorbs liquids and resists complete drying, which encourages mold growth. If you use a reusable straw, cleaning it the same day is not optional, and letting it air-dry fully before capping or storing it prevents the damp conditions that bacteria prefer. A dedicated straw brush costs almost nothing and is the single most important accessory for anyone who has made the switch from disposable.