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Paleo Hydration

On Paleo, it’s easy to focus on food – what foods and how much to eat, when to eat them, (or not to eat them), and where to get them. But food isn’t the only kind of nourishment that you get through your mouth: water is just as important, if not more so. By weight, the human body is more than 50% water, and we need it for everything from good digestion to healthy skin. This means that dehydration and overhydration both have serious health consequences, and water contaminated with any kind of toxins or chemicals will spread the damage through every cell in your body. The quantity and the quality of water you drink can be just as important as the food you eat – but unfortunately, there’s just as much misguided “common knowledge” about water as there is about food.

8 Glasses a Day?

Anyone who’s ever encountered a dietitian knows the standard advice: 8 8-oz glasses of water per day. This is very well-meaning advice, but unfortunately inaccurate – even the CDC doesn’t insist on such a simplistic prescription. For one thing, the 64-ounce mandate isn’t actually based on any evidence; for another, even the original recommendation (from a set of 1940s nutrition guidelines) didn’t actually specify 8 cups of pure water every day. Instead, it acknowledged that the water in foods (especially soups and vegetables) could count towards the recommended daily intake. The insistence that we all need to drink 64 ounces of water a day in addition to everything we already get from our food is nothing but an inaccurate misstatement of an outdated opinion.

So how much water do we actually need to drink? People’s true water needs vary widely – body weight, nutritional needs, age, and activity levels all affect the amount of water someone needs every day. A 16-year-old male athlete who pushes himself through 2 hours of an intense soccer game in the sun will have very different water needs from his grandmother who sits in the shade and watches.

Fresh glass of waterSince water needs are so variable and difficult to measure, trying to pin down a magic number of ounces per day is an exercise in futility, especially because healthy adults already have a built-in system for regulating water intake and maintaining healthy fluid levels in the body. Essentially, your body has to balance the amount of water you excrete with the amount you drink, to keep a constant ratio of water to other substances in your body fluids. The osmolarity (the concentration of other substances) of the body fluids signals the body to conserve or excrete water. A high concentration of salt in the blood, for example, causes you to feel thirsty, and signals the kidneys to conserve more water, rather than excreting it through urine. When you’ve drunk enough to balance your water and salt levels again, the thirst fades and the kidneys are free to excrete any excess water. For healthy adults who aren’t living in extreme climates or participating in endurance sports, this natural system keeps the body in fluid homeostasis, maintaining healthy water levels throughout the day. To drink enough water, simply listen to your thirst.

Disobey your Thirst (Sometimes)

Although most people can rely on thirst as an indicator of when to drink, it is sometimes necessary to drink more, to avoid the risk of dehydration. Athletes who engage in very intense activity (and lose a lot of water through sweat) often need more water than they might feel thirsty for. This is especially true if you’re exercising in the heat. Elderly people also often have trouble relying on their body’s natural thirst cues. Thirst in general decreases with age, but the body’s needs for water may actually increase, as kidney function declines. Many elderly people also have physical trouble getting a drink when they need one, causing them to drink less than they should. These problems can cause dehydration and hypernatremia (elevated blood sodium levels).

As anyone who’s suffered through a bout of food poisoning knows, temporary illnesses can also cause dehydration. Any disease that causes diarrhea or vomiting can drain your body of fluids very quickly, and, if you’re feeling sick and nauseous, you might not feel the urge to drink as much as you need. Throat infections can also cause dehydration by making swallowing painful and difficult.

Unfortunately, not drinking when you’re sick is just kicking yourself while you’re already down. Even mild dehydration isn’t a problem anyone wants to deal with. Chronically low water intake puts an intense stress on your kidneys. Since the kidneys’ job is to filter toxins out of your body and excrete them in the urine, not drinking enough water makes it harder for your body to deal with any toxins that you might have ingested. It’s also one of the greatest risk factors for kidney stones, a treatable but very painful problem that nobody wants to deal with.

Another less serious but irritating side effect is chronic constipation: if you don’t get enough water, your intestines absorb as much as possible of whatever you do drink, leaving the feces dry and compacted. Not getting enough water can also hamper your weight loss efforts – since many people confuse hunger and thirst, you might be tempted to eat more when you’re actually thirsty. And unless you eat a food very high in water (like cucumbers), chances are that once you’ve eaten, you’ll still be thirsty, so you won’t feel satisfied.

Dehydration is a serious problem, but fortunately it’s completely avoidable: drinking enough fluids can prevent it entirely. A water bottle or drinking glass at your desk can remind you to drink more regularly if you have trouble remembering to get enough water. If you’re sick and struggling to keep anything down, bear in mind that “fluid” doesn’t necessarily have to be water: hot tea or bone broth will be just as hydrating, and might be easier on your stomach. Bone broth also contains many beneficial nutrients, making it an excellent choice of comfort food for a nasty flu.

Dehydration is bad enough, but overhydration isn’t any better. Some groups of people are actually prone to overhydrating (drinking more water than the body can healthily process and excrete), and need to watch their water intake accordingly. The elderly are at high risk for a disorder called SIADH (Syndrome of inappropriate secretion of antidiuretic hormone), a problem that prevents the kidneys from excreting enough water. This puts older adults at risk of overhydration. People with heart, kidney, or liver disorders may also be at risk of overhydration, because the organs involved in maintaining their fluid balance aren’t working properly. In these situations, it’s generally preferable to treat the underlying cause, rather than attempt to treat the symptoms by restricting water intake.

Ironically, people trying to avoid dehydration are also at risk of going too far in the opposite direction: anyone making an effort to drink a very large amount of water needs to be very careful to get enough sodium and potassium in their diet, to avoid overhydration. These minerals are two of the most important electrolytes, electrically charged minerals in your blood that help regulate blood pH and muscle function, among other important processes. Drinking too much water without also getting enough electrolytes can dilute the concentration of sodium in your blood to dangerous levels, a condition called hyponatremia. Your cells become swollen with the excess water: most of your body can handle this without a problem, but your brain cells can’t, so brain swelling has the potential to become very dangerous. Symptoms of hyponatremia begin with lethargy and confusion, and can progress to muscular problems and even seizures if the condition isn’t treated. In very extreme cases, water poisoning can actually be fatal. It’s important not to drink so much water that you overwhelm the balance of water and electrolytes: try choosing coconut water as part of your post-workout rehydration (or for a DIY Paleo electrolyte drink, see the section below on water recipes).

Water Purity and Toxins

After putting so much time and effort into eliminating toxins from your food and your environment, you don’t want to just get all the same bad guys from a different source! Toxic chemicals in the water supply are unfortunately very common – a 2009 report on water quality across the US found that tap water contained 97 agricultural pollutants, 204 industrial chemicals, 86 chemicals connected with urban runoff, and 42 toxic chemicals added during the water treatment process. Some (like agricultural pollutants) are there by accident, but others (like chlorine) are actually added deliberately as purification agents. Disinfectant chemicals prevent bacteria from contaminating the drinking water supply, but unfortunately, they can’t differentiate between you and E. Coli. The concentration of chlorine in your tap water might not be strong enough to kill you the way it does bacteria, but that doesn’t mean it isn’t harmful.

Common tap water disinfectants include chlorine, chlorine dioxide, chloramine, and ozone. None of these chemicals are good for you as it is, but to make matters even worse, they can also react with minerals and organic materials in the source water to form Disinfection By-Products, or DBPs. DBPs include several different types of chemicals, depending on which disinfecting agent was used in the original water. For example, chlorine (the most widely used disinfectant chemical) reacts with organic materials like decaying plants to form various different DPBs. Several of these unsavory characters are suspected carcinogens, and regulated as toxic, but not all of them are even identified, much less studied in any detail, regularly measured, or regulated at all.

Another chemical commonly found in tap water is fluoride, a chemical commonly added to municipal water supplies to prevent tooth decay. Although the American Dental Association claims that fluoride is safe at the levels added to tap water, the topic is very controversial, and opponents of fluoridation claim that fluoride is linked with health problems including bone problems, gut irritation, thyroid dysfunction, and cancer. Although it’s unlikely to be a communist plot (as some people actually believed during the Cold War), it’s probably not necessary for dental health and it is potentially harmful.

Fearing the possible chemical contents of tap water, many people turn to bottled water as somehow more hygienic or safer, but in fact, bottled water regulations are based on the same set of standards as tap water regulations (with the only exception of lead standards, which are stricter for bottled than for tap water, because bottled water doesn’t have to pass through old pipes), and most bottled water doesn’t contain any more minerals than ordinary tap water. In fact, some bottled water is nothing but tap water in a bottle: you’re essentially paying $2 a pop for the same drink you could get almost free from your own kitchen sink. Many bottlers do use alternate methods of purification, rather than chlorine, but drinking out of a plastic bottle raises an entirely new set of concerns about BPA exposure, so drinking bottled water is far from a surefire way of avoiding toxins. Of course, bottled water is also much more expensive and environmentally destructive (especially since many people just throw away the bottles instead of recycling them).

Since bottled water isn’t really better, on average, than tap water, it’s not worth the trouble and expense of buying it. Instead, the best way to avoid water toxins is to either get water from a known pure source (a private well), or use some kind of water filter to purify what comes out of your tap. Private well water is fantastic if you have access to it (since there are no added disinfectant chemicals, you won’t get the negative side effects of the chemicals or the DPBs), but not everybody can reliably reach a well on a regular basis. And even if you can, it’s usually a good idea to filter your well water anyway, to remove any pesticide runoff or other environmental pollutants that might be contaminating it. Nobody dumped a load of chlorine into your well, but that doesn’t mean it’s toxin-free.

Since even well water isn’t guaranteed to be free from all contaminants, the best way to avoid water toxins is to simply filter them out yourself. Dozens of water filters (from whole-house filters to water bottles with filters built in) are available on the market; which particular filter you chose will depend on your specific situation. If you own your own home and have enough time and money, whole-house filters are very convenient once installed and take care of your sinks and shower all at once. For people who can’t afford the investment or for some reason can’t make that big of a change to their living space, a variety of external filters are available.

When choosing a water filter, first check with your municipality to see specifically what chemicals are added to your water: for example, not all areas fluoridate their water, and there’s no point spending time and energy filtering out a chemical that was never there to begin with. A slight smell or “off” taste doesn’t necessarily indicate the presence of chemicals, either: it’s more likely to be a sign of beneficial trace minerals. You should also check your plumbing: the lead pipes in older buildings can sometimes pose a health risk as well.

Once you’ve determined what you need to filter for, you can choose your plan of attack. Granular Activated Carbon (GAC) technology filters out chlorine and DBPs, but GAC filters do not effectively remove fluoride; if you’re concerned about fluoride in your drinking water, distillation units or reverse osmosis filters will remove it. Many people recommend Berkey water filters as cost-effective, efficient, and convenient – the standard filters can handle chlorine and other pollutants, and you have the option of adding a special fluoride filter.

Of course, after taking so much care to remove toxins from your water, it’s also important not to put them right back in! Plastic cups and water bottles contain BPA and other environmental estrogens; try to drink out of glass, ceramic, or stainless steel containers rather than plastic.

Water and Toxins: Think Outside the Glass

Although drinking water is probably the most important way that most of us are exposed to chemicals like chlorine and chloramine, we’re all also exposed to the same water when we shower, bathe, or jump into a swimming pool. In fact, chlorine from shower water might actually be more dangerous than chlorine from drinking water: in the shower, you’re exposed to chlorine gas by breathing in steam, and the gas that enters your lungs goes straight to your bloodstream. The water in a public pool isn’t hot, which reduces this effect, but it also contains a much higher concentration of chlorine, and who hasn’t accidentally swallowed a gulp of pool water once or twice? The lack of ventilation in many indoor pools can make this problem even worse – several studies have linked chlorine levels to respiratory symptoms in regular swimmers. Saunas and hot tubs, of course, are both heated and highly chlorinated.

This doesn’t necessarily mean that you need to stop swimming – some pools have actually switched to less toxic disinfectants because of concern over the dangers of chlorine, so your local facility might not present a problem in this respect. Also, it’s important to note that most of the studies on the dangers of chlorine toxicity were done on competitive swimmers, who spend much more time in and around pools than the rest of us. Since everyone (hopefully!) showers every day, buying a dechlorinating filter for your showerhead is a smart move, but there’s no reason to be seriously concerned about the occasional trip to the pool. Unless you’re very sensitive to chlorine, the benefit you get from the exercise will outweigh the potential dangers of the toxins. If you’re seriously concerned, showering before entering the pool can also help prevent the formation of DBPs in pool water, since it removes any dirt on your skin that the chlorine could react with to form toxic byproducts.

Water Recipes

Your water might be as pure and toxin-free as the first trickles off a Cryogenian glacier, but there’s a reason why flavored drinks have such a huge market: sometimes, plain water could use a little variety. Once you re-train your taste buds to stop relying on artificial sweeteners and fizzy soft drinks, pure water does taste delicious. But even people who willingly drink plain water sometimes like a little enhancement, and Paleo-friendly water flavorings can do a lot to ease the transition away from Coke and Kool-Aid.

For pure flavorings, mint and cucumber are classic favorites. Add them to a pitcher of cold water, and let it chill for a few hours before serving. Citrus juice (lemon or lime) is also delicious, and the visual appeal of citrus fruit makes it a beautiful addition to a water pitcher for a dinner party. To make a Paleo sports drink, try adding a pinch of salt to some citrus-flavored water: this adds essential electrolytes to your post workout (or pre-workout) hydration. Coconut water is another delicious form of natural Gatorade; just make sure to get a kind without added sugars, and preferably not from concentrate. Or, for a truly Paleo experience, find yourself a fresh young coconut (these are sometimes available at Asian markets, even though they aren’t common in regular grocery stores) and get the coconut water straight from the source.

Coffee and tea are also many people’s favorite ways to get enough fluids. There’s nothing wrong with either of these, but it may be wise to moderate your coffee and tea consumption for several reasons. Any kind of beverage with caffeine in it can leave you jittery and wound-up if you drink too much of it, and caffeine can seriously affect your regular sleep cycles even after the “buzz” has worn off. Thus, regular coffee and any kind of caffeinated tea are best avoided in the afternoon and evening. It’s also important to make sure you aren’t sabotaging your health with what you’re adding to your mug: coffee is Paleo; artificial creamer powder is not. And that triple grande no-foam no-whip half-caf soy latte with three pumps of sugar-free hazelnut is definitely out.

On the other hand, a delicious and 100% Paleo way to enhance your coffee is to make it bulletproof: add grass-fed butter and MCT oil to your morning brew for a satisfying breakfast drink full of healthy fats. Adding whole-fat dairy is also fine if you tolerate it well (or coconut milk, if dairy isn’t an option); cinnamon or other spices can also add a flavor boost.


Water is one of the most basic substances in the world – and drinking enough water is one of the best things you can do for your health. Staying hydrated has benefits for everything from your skin tone to your kidneys. This doesn’t mean that you need to guilt yourself into drinking any set amount or constantly “rehydrate” even when you aren’t thirsty, but if you’re at risk of dehydration for any reason (especially from very intense athletic training), stay aware of your water intake and make sure you’re drinking enough fluid and electrolytes to keep your body in peak condition.

Municipal water is often pumped full of toxic antimicrobial agents that produce even more harmful byproducts, but proper filtration systems can remove these chemicals, leaving you with fresh, delicious water to enjoy plain or with your choice of natural flavorings. That said, it’s important not to get carried away with worry about every problem you can possibly imagine. Some people are very sensitive to chlorine or fluoride, but most of us won’t see any ill effects from drinking out of a plastic bottle or a public water fountain in a pinch. If you’re truly passionate about clean water, try getting involved with local activism: joining an anti-fracking group or an organization advocating safer water treatment methods in your area. This will do a lot more good than worrying yourself sick about pesticide runoff or DBPs, and you might even have a good time along the way.