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.

Could there be a diet that allows you to eat more and still helps you lose weight? For the longest doctors and health experts praised the Mediterranean diet. This is because it is heart-friendly, and has a mix of fruits, whole grains, vegetables, and sea food. However, new research suggests that even a simpler diet would work better. As per British scientists, by simply cutting out ultra-processed foods, and sticking to unprocessed whole foods could lead to greater calorie reduction and weight loss.

Eating More, And Still Losing Weight? What Is Working

The key is to reduce the intake of calories, which is possible when you cut your ultra-processed foods. In a study, researchers found that people who followed a completely unprocessed diet consumed around 330 fewer calories per day than those who ate more processed food.

What surprised scientists was that participants actually ate more food by volume. Those on the whole-food diet consumed about 57 percent more food overall, yet still ended up eating fewer calories. The reason lies in the type of foods they chose, such as fruits, vegetables, salads, and lean proteins, which are naturally lower in calorie density.

This means people could eat larger portions, feel full, and still reduce their total energy intake.

Read: Ultra-Processed Foods May Add 330 Extra Calories A Day, Study Finds

Why Are Ultra-Processed Foods Problem?

Ultra-processed foods, often called UPFs, include items like ready meals, packaged snacks, sugary cereals, sweets, and hot dogs. These foods are typically high in calories, sugar, unhealthy fats, and additives, while being low in fiber and nutrients.

Ultra-processed foods, engineered with additives, preservatives, and artificial ingredients, now comprise over half the average American diet, based on data from the U.S. Department of Agriculture. Their ubiquity and intensive marketing have made them seem inevitable, but accumulating evidence indicates that the health toll is much more serious than realized.

Under the NOVA food classification system, UPFs are defined by their intensive industrial processing, which is typically used to produce hyper-palatable and highly profitable foods. Yet, the convenience comes with an increasingly large body of evidence showing that these foods contribute to a variety of chronic diseases, including cardiovascular disease, obesity, diabetes, depression, and various forms of cancer.

Researchers say UPFs may quietly push people towards overeating without realizing it. Even small portions can contain a large number of calories, making weight gain more likely over time.

The study suggests that when people are given the option to eat foods in their natural or minimally processed form, they tend to make smarter choices on their own.

Also Read: Are All Ultra-Processed Foods Bad For You? Experts Say Some Are Better Than Others

How Was The Study Conducted?

The research followed 20 overweight adults, including 10 men and 10 women, with an average age of 31. Participants were divided into two groups.

One group followed a two-week diet based on minimally processed foods such as vegetables, fruits, salads, and lean meats. The other group ate a diet rich in ultra-processed foods like hot dogs and ready meals. After two weeks, the groups switched diets.

Importantly, the meals were matched for nutrients such as fat, protein, carbohydrates, salt, and fiber. Despite this, those eating whole foods consumed fewer calories and lost nearly one kilogram in weight.

Feeling Fuller and Reducing Cravings

Researchers believe fruits and vegetables played a key role. These foods are high in water and fibre, which lowers their energy density. As a result, people can eat more without consuming too many calories.

Experts also point out that natural fiber helps people feel full for longer and supports gut health. Fibre can trigger hormones that regulate appetite, reducing cravings and helping with long-term weight control.

What This Means for Everyday Diets

The findings add to growing evidence linking ultra-processed foods to a range of health problems. Studies have previously associated high UPF intake with dozens of illnesses.

In the UK, ultra-processed foods make up about 57 percent of the average diet, one of the highest levels in Europe. Experts recommend that around 80 percent of daily food intake should come from whole or minimally processed foods.

The message from scientists is simple. You do not need complicated diet rules. Choosing foods closer to their natural form may help you eat better, feel fuller, and lose weight more sustainably.

A small study suggests that people who avoid ultra-processed foods (UPFs) consume around 330 fewer calories each day on average—even while eating more by weight. Researchers say that when food is offered in its natural, unprocessed form, people tend to make “much smarter decisions.”

The study, conducted by the University of Bristol, reanalysed data from a U.S. clinical trial with 20 participants, which had found that eating only UPFs leads to overeating and weight gain. The team discovered that people eating solely whole foods naturally chose fruits and vegetables over higher-calorie items like pasta and creamy dishes.

Also Read: 11 Brain And Nerve Symptoms Neurologists Say Can Become Life-Threatening

Ultra Processed Foods: What Are They?

Ultra-processed foods are ready-to-eat products made in factories using industrial methods. They rely on chemically modified ingredients and additives rather than whole foods, and often contain little to no real nutrition. Instead, they are loaded with sugar, saturated fats, and salt, which can contribute to chronic health problems over time.

Ultra Processed Foods: How Whole Foods Change Eating Habits

According to the study, as per The Independent, people avoiding UPFs ate 57% more food by weight. Jeff Brunstrom, professor of experimental psychology at the University of Bristol, explained: “It’s exciting to see that when people are offered unprocessed options, they instinctively select foods that balance taste, nutrition, and satiety while still reducing overall calorie intake. Our dietary choices aren’t random—when food is in its natural state, people actually make smarter decisions than we expected.”

Ultra Processed Foods: Common Examples

According to NOVA, ultra-processed foods are ready-to-eat or ready-to-heat products made mostly from industrial ingredients and additives, rather than whole foods. Common examples include:

• Chips
• Carbonated drinks
• Instant noodles
• Ice cream
• Chocolate
• Biscuits
• Sauces and instant sauces
• Ready-made meals
• Mass-produced packaged bread
• Sausages and hot dogs
• Burgers
• Chicken and fish nuggets
• Instant soup
• Meal replacement shakes and powders
• Candy
• Pastries
• Fruit yoghurt
• Fruit drinks
• Cake mix
• Margarine
• Sweet or savory packaged snacks
• Energy bars

These foods are often high in sugar, salt, and unhealthy fats, and low in natural nutrients.

Ultra Processed Foods: Vitamin Fortification Can Mislead

The research also highlighted a concern: some UPFs meet micronutrient requirements through fortification. For example, pancakes and French toast sticks contained vitamin A. However, participants consuming only whole foods got their vitamin A from carrots and spinach, which are far lower in calories.

Ultra Processed Foods: The Calorie-Micronutrient Trade-Off

Dr. Annika Flynn, senior research associate at the University of Bristol, said: “This suggests that UPFs can deliver both calories and nutrients in a single product, which may lead to overconsumption. Whole foods, on the other hand, maintain a healthy balance, encouraging people to favour nutrient-dense options like fruits and vegetables instead of high-calorie foods such as pasta and meat.”

Ultra Processed Foods: Why This Matters for Everyday Eating

The findings underline how simple changes—choosing minimally processed, whole foods—can naturally reduce calorie intake without feeling restrictive. By letting people eat more volume while cutting energy intake, whole foods may help manage weight and improve overall nutrition.

Health specialists have cautioned that a widely used dairy milk alternative may come with downsides many people are unaware of, especially when consumed first thing in the morning, according to Mirror. Oat milk, a popular plant-based and dairy-free option, is often praised for its fibre content and for being fortified with calcium and vitamin D, both important for bone health. However, dietitians point out that compared to other plant-based milks such as almond milk, oat milk tends to contain higher amounts of carbohydrates, added sugars and oils.

What Is Oat Milk Made Out Of?

Oat milk is a dairy-free, plant-based drink that is commonly valued for its fibre content and added calcium and vitamin D, which support bone strength. That said, health experts note that it generally contains more carbohydrates, sugars and oils than many other plant milks, including almond milk.

Registered nutritionist Jenna Hope explains that oat milk is usually produced by creating a syrup from oats, which is then mixed with water. She adds that many well-known oat milk brands also include added oils, emulsifiers and stabilisers to improve texture and shelf life.

Why Is Oat Milk Bad For Your Health?

Experts say certain aspects of oat milk may negatively affect health, particularly when consumed on its own. Speaking to Parade, registered dietitian Melissa Rifkin said that while oat milk lattes can fit into a healthy diet, they are not nutritionally complete by themselves. She noted that although oat milk offers some fibre, most oat milk lattes are low in protein and fat, two nutrients that help regulate blood sugar levels and promote fullness.

Sharing a similar view, registered dietitian Nour Zibdeh told The Independent that oat milk’s high carbohydrate content can lead to sharp rises in blood sugar when consumed in the morning. This effect is less pronounced with dairy milk, which naturally contains protein and fat that help balance its sugar content.

Ms Zibdeh also told Parade that oat milk is low in protein and fat, which contributes to greater blood sugar spikes. French biochemist and author Jessie Inchauspé, widely known as the “Glucose Goddess”, has also criticised oat milk. In a 2024 interview with American entrepreneur Marie Forleo, she described oat milk as similar to drinking “starch juice”, explaining that oats are a grain and grains are primarily made up of starch.

Should You Replace Oat Milk With Cow Milk?

Overall, nutrition experts tend to agree that cow’s milk offers greater nutritional value. Regular dairy milk intake has been linked to better metabolic and heart health, and cow’s milk contains higher levels of key micronutrients such as phosphorus, which supports healthy bones and teeth, along with calcium, vitamin D, B vitamins and potassium, compared to oat milk.

That said, cow’s milk is not suitable for everyone. Allergies, taste preferences and vegan diets mean many people rely on plant-based alternatives. If oat milk is your preference, there is no need to panic. Experts stress that moderation is key and that oat milk can still be enjoyed as part of a balanced diet.

Choosing oat milk does not mean it needs to be completely removed from your routine. There are simple ways to enjoy it while being mindful of expert advice. For those who love an oat milk latte, pairing it with protein-rich foods such as eggs or Greek yoghurt can help balance blood sugar levels and make the meal more satisfying.