You've probably asked yourself too if that old bottle of water in your pantry is still good to drink? Water is life, yet there are remaining questions about the shelf life. Whether you are stockpiling for emergencies or wondering if that bottled water left in a heated car is safe to drink, understanding if and how water "expires" is essential. This article goes into the science behind water storage and its potential risks and practical tips to ensure your water will remain safe and consumable.

Water itself does not spoil or degrade. Chemically, pure water (H₂O) remains unchanged indefinitely. However, there are issues that arise due to the containers in which it is stored and the environmental conditions surrounding the storage.

In the United States, most bottled water has an expiration date. This labeling is often misunderstood as being an indication of the water's safety, but it mainly has to do with quality. The U.S. Food and Drug Administration (FDA) confirms that commercially sealed bottled water is safe to drink indefinitely if stored properly. Over time, though, the taste, smell, and even the appearance of water may change due to interactions with its packaging.

Role of Packaging in Water Safety

Plastic Bottles and Chemical Leaching

Bottled water is mostly packed in polyethylene terephthalate, PET plastic. Even though it is light in weight, resistant, and recyclable, this material is limited in other aspects. It leaches chemicals in trace amounts in the water if heated or placed under direct sunlight. For instance, do not leave your bottled water in the hot car for an extended period.

The next is bisphenol A or BPA. This chemical has been used to soften some plastics and is known for its hormone disruption. Many producers have shifted toward BPA-free materials, but older bottles and improper storage still pose risks. Bottles carrying recycling code #7 may be BPA-contaminated. There are also concerns over microplastics and long-term storage.

Microplastics and Long-Term Storage

Over time, the plastic in the bottle may leach into the water, causing some to question health risks. In 2019, one article published in the International Journal of Environmental Research and Public Health noted that these particles exist but are usually not at high enough concentrations to pose a problem if the water is properly stored.

Also Read: What Happens When You Drink Too Much Water?

How Long Can Water Be Stored Safely?

Bottled Water

Unopened bottled water, kept in a cool, dark place, remains safe to drink for years. But manufacturers often advise that it should be consumed within two years of its manufacture date for best quality. After this period, it may start showing off-flavors or odors due to contact with the plastic.

Tap Water

Tap water, under the Environmental Protection Agency (EPA), undergoes strict standards for safety. It can be kept in pure, BPA-free bottles up to six months. Afterward, it loses its fresh flavor or becomes dirty if not properly sealed.

Rainwater

Don't drink rainwater unless treated first. It usually contains contaminants that should not reach the human stomach. It should be used to water plants if not filtered and sterilized first.

Signs That Water Has Gone Bad

Water itself doesn't go bad, but extrinsic factors make it unsafe. Always discard water that has:

An off smell: An earthy, metallic smell indicates contamination.

Coloration: Greenish or bluish coloration signifies microbial growth or rust.

Unpleasant taste: A metallic or stale taste is a hallmark of degradation.

Froth or particles: Indicate dirt, germs, or other impurities.

How to Store Water Safely?

Avoid Heat and Sunlight

Store water in a cool, dark place and out of direct sunlight. Heat breaks down the plastic, allowing chemicals to leach out more easily.

Choose the Right Containers

For long-term storage, select BPA-free or food-grade plastic containers. The best alternatives are stainless steel and glass containers, which avoid all the risks that plastic poses.

Hygiene Maintained

Wash and sanitize the container before refilling. Always seal the lids so that no bacteria get inside.

Rotate Your Stock

Use a first-in, first-out rotation system with stockpiled water. This will mean that you will use the oldest water first to keep your water supply fresh.

Is It Safe to Drink Water Past Its Expiration Date?

The expiration date on bottled water is a mark of its quality, not safety. Although the water is safe to drink past this date, it is sensible to check it for any signs of spoilage as mentioned above. Tap water that has been stored for longer periods should be checked for clarity and odor before consumption.

Plastic bottles, although convenient, degrade the environment. Only a few percent of PET bottles are recycled, while the rest remain in landfills or oceans. Choose reusable containers and tap water whenever possible to minimize plastic waste and environmental damage.

Water is one of the most precious resources in this world, yet it can be safe only if it is kept appropriately. People may tell you that water does not expire, but the fact is that packaging materials, exposure to the environment, and storage conditions may affect the quality of the water. Proper storage techniques, opting for BPA-free containers, ensure that water remains fresh, safe, and ready for consumption at any time.

High-protein diets have become increasingly popular among fitness enthusiasts and health-conscious masses.

However, a new scientific review suggests that many adults, particularly those who are sedentary, maybe consuming more protein than they actually need.

The study also shows that eating less protein rather than more may support healthier ageing by improving metabolism and reducing age-related biological changes.

Are Low Protein Diets The Key To Live Longer?

The review, published by Cell Press, studied data from more than 350 studies investigating how dietary protein affects ageing and metabolic health.

Researchers concluded that reducing overall protein intake, or restricting certain amino acids like methionine, isoleucine, and valine, activates biological pathways linked to better metabolic function, cellular maintenance, and lower inflammation.

According to the researchers, several of these benefits appear to be driven by fibroblast growth factor 21 (FGF21), a hormone that rises when protein intake falls.

Higher FGF21 levels have been associated with better insulin sensitivity, better blood sugar regulation, increased energy expenditure, and healthier ageing in experimental models.

Lead author Dr Dudley Lamming, professor at the University of Wisconsin-Madison, said the growing popularity of protein-enriched foods may not benefit everyone.

"Our review suggests that reducing protein intake, rather than calories, may provide many of the same metabolic benefits while being easier for people to follow," the research team noted, adding that protein recommendations may need to be tailored according to an individual's age and physical activity rather than using a one-size-fits-all approach.

Also read: Do Most Adults Eat More Protein Than They Need? New Review Challenges The 'High-Protein' Trend

Excessively High-Protein Diets May Increase Metabolic Burden

HealthandMe spoke to Dr. Mukesh Thakur, Director - Internal Medicine, Acute Medicine & Clinical Transformation, Sir H. N. Reliance Foundation Hospital, to find out who should and should not cut back on protein to improve longevity.

The doctor says that protein is essential for maintaining muscle mass, supporting immune function, and promoting overall health.

Dr Thakur says, "The optimal amount of protein varies depending on factors such as age, overall health status, and, most importantly, an individual's level of physical activity. For people who are largely sedentary, consuming very high amounts of protein may not offer additional health benefits."

He added that if the excess protein consumed is not utilized to build or maintain muscle through regular physical activity, it may contribute to excess calorie intake and increase metabolic stress.

He also explains, "Emerging research also suggests that chronically high protein intake, particularly from animal sources, may overstimulate biological pathways such as IGF-1 and mTOR, which have been linked to accelerated ageing in experimental studies."

To sum up, for individuals with obesity or diabetes, excessively high-protein diets can be particularly concerning, as they may increase the metabolic burden and are not necessarily associated with better health outcomes.

Conclusion

The researchers caution that the findings should not be interpreted as a recommendation for everyone to reduce protein intake.

While sedentary adults consuming excessive protein may benefit from moderation, adequate protein remains essential for older adults, athletes, pregnant women, children, and people recovering from illness or surgery to maintain muscle mass and overall health.

Today, protein has found its way into everything from coffee and cereal to chips and even water. But a new scientific review suggests that for many adults, especially those who are not physically active, consuming more protein than needed may offer little benefit and could even have pose unintended health consequences.

Published in Cell Press Blue, the review analyzed more than 350 studies on restriction of protein, aging, metabolism, and longevity across humans and animal models.

Researchers concluded that while protein remains essential in one's diet, most sedentary adults are likely consuming more than they need. It also found that bringing down excess protein intake may support healthier aging.

“It’s absolutely crystal clear that there are benefits of protein to muscle growth and exercise response of active individuals,” said Dr. Dudley Lamming, aging researcher at the University of Wisconsin-Madison and the review’s corresponding author.

“But because most people are relatively sedentary, many people are likely consuming more protein than they actually need, which probably has negative health consequences,” he added.

Can Eating Less Protein Help?

The researchers explain that eating less protein appears to activate several biological pathways that are associated to healthy aging.

One key player is fibroblast growth factor 21 (FGF21), a hormone that rises when protein intake is reduced.

Higher FGF21 levels have been associated with increased energy expenditure, better blood sugar control, lower inflammation, and healthier metabolism. Animal studies have also linked elevated FGF21 to longer lifespan.

The review also highlights specific amino acids, including methionine, isoleucine, and valine, which may influence aging-related processes when consumed in excess. Restricting these amino acids appears to alleviate cellular stress and improve metabolic health in experimental studies.

Also read: No Junk Food Near Schools! Maharashtra FDA Bans Sale Of Foods & Drinks High In Fat, Salt & Sugar

Researchers caution that the findings do not mean everyone should start eating a low-protein diet.

Protein requirements vary depending on age, activity level, health status, and life stage. Athletes, pregnant women, people recovering from illness or surgery, and many older adults often require more protein for muscle maintenance and recovery.

“Recent recommendations have encouraged people to eat more protein, but they’ve also encouraged people to exercise more,” Lamming said. “We probably need to personalize protein recommendations based not just on age, but also on how physically active people are.”

How Much Protein Do Adults Actually Need?

For healthy adults, the recommended dietary allowance is 0.8 grams of protein per kilogram of body weight daily. Although individual needs increase with regular exercise, aging, pregnancy, or certain medical conditions.

Many adults already exceed these recommendations through regular meals alone, even before adding protein supplements.

The researchers acknowledge that much of the evidence comes from animal studies, and long-term human trials are still limited. They say future research should determine exactly who benefits from lower protein intake and who needs more.

As protein-fortified products continue to flood supermarket shelves, the researchers argue that dietary advice should become more personalized rather than assuming higher protein intake benefits everyone.

Ultra-processed foods (UPFs), typically high in salt, sugar, and unhealthy fats, have long been associated with obesity, diabetes, hypertension, and other chronic diseases.

Now, new research suggests that the vast majority of foods marketed for toddlers in the US fall into this category. A study led by the University of Texas at Austin found that more than 80% of toddler foods sold in US grocery stores are ultra-processed, while nearly half fail to meet at least one nutrient standard set by the World Health Organization (WHO) for commercial foods intended for children aged 6 to 36 months.

Majority Of Toddler Foods Are Ultra-Processed

Also read: Can Your Child’s Diet Shape Future Diabetes Risk? Study Links Ultra-Processed Foods To Early Insulin Responses

Researchers analyzed 2,783 toddler food products sold across 21 grocery stores in Texas. Using the Nova classification system, they found that 81% of products were ultra-processed, while 49% failed to meet at least one WHO nutrient standard.

Among the products analyzed:

• 81% were classified as ultra-processed.
• 17% exceeded WHO recommendations for sugar.
• 25% exceeded recommended sodium levels.
• 11% exceeded recommended fat levels.
• 12% exceeded recommended energy density.

Products that exceeded WHO recommendations included:

• Fruit pouches (high in sugar)
• Oat bars (high in sugar and calories)
• Mac and cheese (high in sodium and fat)
• Turkey sticks (high in sodium and fat)
• Cheese puffs (high in calories)
• Peanut butter puffs (high in sodium, fat, and calories)

“Many parents may assume that products sold on the baby/toddler food aisles of their grocery stores have to meet certain nutrient standards. Our findings highlight that half of the toddler foods available in local grocery stores do not,” said Erin A. Hudson, a University of Texas at Austin graduate student and science policy fellow with the American Society for Nutrition.

Hudson urged parents "to be vigilant in checking labels and ingredients to determine the nutrient content and processing level of products for their toddlers".

Read More: 'Let's Fix Our Food': India Launches New Policy To Fight Childhood Obesity, Boost Nutrition

Why Is This Concerning?

The toddler years are a crucial period for developing lifelong eating habits and taste preferences. Diets high in added sugars and ultra-processed foods during early childhood may increase the risk of obesity, diabetes, cardiovascular disease, and other chronic illnesses later in life.

The researchers found that ultra-processed toddler foods were significantly more likely to be high in sugar than less-processed alternatives. Excess sugar intake in young children has been consistently linked to poor health outcomes, including obesity and metabolic disorders.

The findings come as the US Food and Drug Administration (FDA) is considering new guidelines for front-of-package nutrition labels, healthy claims and marketing of food products to children. The US currently does not require warning labels on any food products that are high in sugar, sodium or calories.

What Are Ultra-Processed Foods?

Ultra-processed foods (UPFs) are industrially manufactured products made with ingredients and additives rarely used in home cooking, including preservatives, emulsifiers, artificial sweeteners, colorants, flavor enhancers, and hydrogenated oils. They are generally high in refined carbohydrates, added sugars, unhealthy fats, and sodium, while being low in fiber and other essential nutrients.

Research suggests that diets high in UPFs may promote chronic inflammation, disrupt the gut microbiome, and impair insulin regulation over time, potentially increasing the risk of obesity, type 2 diabetes, cardiovascular disease, and other chronic illnesses from an early age.