On the agenda for today: does drinking enough water really help with a weight loss goal?
It’s easy to think about building your plate the right way, getting your movement in, and all the other ways we talk about supporting a metabolism, but hydration can sometimes sink to the bottom of the list.
Most people are actually dehydrated. Seriously. Think about it – we slam a coffee or two in the morning, we head out the door, and before we know it, a few hours of our day have started before we even reach for a water.
Or maybe, you do start the day on the right foot with a glass of water, but the rest of the day is pretty hit or miss with remembering to drink more consistently.
Hot take: If you’re not prioritizing your hydration, you might be hindering your weight loss.
Let’s explore this connection:
We know that blood sugar management is essential for weight loss and metabolism. Drinking regular soda, sweet alcoholic beverages, or sweetened iced coffees is just going to spike your blood sugar. Not to mention, excess sugar that we don’t need for energy can add up over time and be stored as fat.
This isn’t to say we can’t enjoy these once in a while, but prioritizing water first and making substitutions more often is helpful in the weight loss game.
More water also means less caffeine and artificial sweeteners. Too much caffeine (yes, 3 cups of coffee is probably too much) has a dehydrating effect and can increase cortisol levels. Why do we care about cortisol? Well, having increased cortisol chronically has a strong relationship with inflammation in the body and can decrease metabolic function. If you want to learn more about cortisol and stress check out this article.
Choosing more water and decreasing beverages with artificial sweeteners (I’m talking to you, Diet Coke) is also very beneficial for two main reasons. One, artificial sweeteners do not directly increase our blood sugar, but they can disrupt the good bacteria in our guts. Compromising our gut health has a role in our metabolic health. Second, artificial sweeteners can lead to cravings. Having that sweet taste can be addicting to some of us and can lead to choosing other sweet things to eat or drink.
Being hydrated means you just feel good in general! You have more energy, mental clarity, and motivation, and you may, indirectly, be less stressed.
I like to think of it as a domino effect. Making sure you’re hydrated first can set you up to feel good and energized so you decide to fit that workout or movement in. You’re able to focus really well at work and crank out that to-do list. Your mid-afternoon slump doesn’t happen so you fit in a relaxing walk outside. By the end of the day, you’re feeling good, not playing catch up, and able to unwind. Talk about bonus after bonus! You’d be surprised how much your hydration status can affect how you feel and what you’re able to conquer in a day.
Considering how much of our bodies are made of water and require it for almost every function, it’s no surprise how important water is for our metabolism to operate. While I won’t bore you with all the scientific details, our metabolic system at the cellular level requires water to be present for almost every step. Simply put, enough water is critical.
For example, when we tap into our stored fat in the body for energy, our bodies go through a process called lipolysis. The first step of lipolysis is hydrolysis, which only happens when water molecules interact with triglycerides (or fat) to separate them into two different components and continue on with the metabolic system.
There is also the conversation of “water-induced thermogenesis.” What does this mean exactly? Well, there is some research showing us that increased water intake can increase our metabolic rate. Drinking more water isn’t going to completely 180 your metabolism, but it is definitely supportive for ideal function!
It’s a fairly common saying: “If you’re hungry, make sure to drink water first in case you are just thirsty”.
While we don’t recommend ignoring hunger cues and sipping on water instead (eating food is the real MVP of decreasing hunger levels), there is some research to support that drinking enough water helps us to tune into hunger cues a little better at meal times.
A small 2018 study found that drinking water before meals helped to naturally decrease calorie intake, which could assist in weight loss. Similarly, a 2016 study found food intake to decrease by 22% when participants drank a glass of water 30 minutes before eating.
If you’re new around here, we don’t believe that “calories in-calories out” is the magical solution to weight loss. But we do recognize that being able to listen to our natural hunger and fullness cues IS very important. Our bodies have internal calorie counters (hello, leptin and ghrelin), and being able to detect those is extremely beneficial to weight maintenance.
Remember, water can never replace our energy needs from food, but ensuring we are properly hydrated prior to meal times can be really helpful in recognizing when our body is truly satisfied vs. additional thirst.
What does gut health have to do with weight loss? Everything!
While the state of our gut health is largely dependent on the foods we eat, the amount of water we drink has also been found to be an important factor.
A 2022 study discussed the importance of drinking plenty of water in shaping the microbiome (out gut environment). While the research looked specifically at how different sources of drinking water impacted gut bacteria, the underlying theme was clear that adequate hydration is associated with improved gut health.
In addition, the study highlighted that high water drinkers also had lower amounts of Campylobacter bacteria, which is linked to gastrointestinal infections. More water = less chance for infection from bad bacteria.
And this makes sense when you think about it. We know that drinking enough water is very important to keep our digestive system moving regularly. Constipation is definitely not beneficial for gut health.
Plus, drinking more water means drinking less alcohol and artificial sweeteners, as mentioned previously. Both have a poor relationship with gut health when consumed too much.
This may seem far-fetched, but our hydration status impacts cortisol levels in the body. For example, one systematic review found participants to have higher cortisol levels even when mildly dehydrated.
What does this have to do with weight loss? More cortisol (AKA the stress hormone) means the body is less efficient at fat loss. High stress on the body can hinder metabolic health.
So, stress management isn’t just about journaling and medication – it can be as simple as drinking enough water too!
We definitely agree by now that hydration is an important part of weight loss, and being consistent with your water intake is going to be really helpful. But how much do you actually have to drink?
You know the 8 cups a day rule? Yea, you can just forget about that. It’s outdated and our hydration needs are all so different.
Because the key word here is HYDRATION. I don’t actually care how much water you drink – I care that you’re hydrated. If you’re just peeing out all the water you drink every day, what’s the point?
A good rule of thumb is the following: Take your weight in pounds, divide it by 2, and that’s the number of ounces you should roughly be drinking each day. So –
150 lb female:
150 / 2 = 75 oz water per day.
But – there’s more to this. When we look at actual hydration, we have to make sure our bodies are actually holding on to the water we’re drinking.
Check out this article for more reasons why you should drink more water.
This is a huge topic that requires a much longer post, however, I do want to mention here how important salt is for our bodies.
We hear too much about how we need to avoid eating too much sodium, keep it less than 2,000mg…you know the drill.
Truth is, as long as you are generally healthy and have no contraindicating advice from your doctor or registered dietitian, we don’t need to be afraid of salt from our balanced diet.
If we don’t have enough salt in our system, the extra water we’re drinking will just be flushed out and our cells do not take it in. If you feel like you’re already drinking tons of water every day but are always thirsty or just not feeling hydrated, you may need to take in a little more salt.
You can do this by actually adding ⅛-¼ tsp of salt to your water once or twice a day. Don’t go crazy, but just add that little bit and see how you feel. I bet many of you will feel more hydrated drinking less water, and you may even notice an energy boost.
More water + enough salt = one hydrated queen.
If you struggle to get your water in, we have so many tips for you! My favorites are:
I bet you didn’t think water was so important for weight loss, did you? Remember, water is not the only thing we have to consider for weight loss, but making it a priority is extremely helpful all around. Let me know your favorite thing you learned in this post in the comments below!
– Elle, MM Coach
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