How much water should I drink to lose weight?

By   Eucalyptus VC


How much water should I drink to lose weight?

We are often told to drink more water when trying to lose weight. 1.5-2 litres is a good goal. But how is drinking water beneficial? And where can you find opportunities to drink more? Here we will look at some of the popular recommendations and discuss the evidence that supports each one.


Have a glass of water before each meal.

Your appetite will ebb and flow throughout each day, and this desire to eat can arise for a variety of reasons. Your body’s physiological need for energy from food can trigger the feeling of hunger, and there is also what we call the gut-brain dialogue that influences our readiness to eat and our fullness. As we fill our stomach, appetite reduces, especially if you eat slowly and tune in to how your stomach is feeling. There are a number of factors that contribute to the sensation of fullness – it can be the nutrients in food, for example protein has been shown to keep you feeling fuller for longer, but it is also related to the physical amount of foods and drinks in your stomach, regardless of their nutrient content. Some studies have shown that a glass of water before a meal can reduce the number of kilojoules you eat at that mealtime. The physical presence of water adds volume to your stomach meaning you’re more likely to feel satisfied sooner and stop eating earlier than you would if you didn’t drink beforehand.

Avoid confusing hunger with thirst.

Another theory behind drinking more water is that perhaps your hunger cues have been confused with the feeling of thirst, and once you rehydrate yourself you may no longer feel hungry.
At a physiological level, our need for food and water is driven by the body’s need for homeostasis –the set point where our body feels in balance. Our decision making when it comes to eating and drinking is often driven by this goal for balance and it happens in the same part of the brain for both thirst and hunger. Animal studies have shown that varying feelings of hunger and thirst can cause confusion in the brain’s choices, such as seeking food when thirsty. Add to this, the fact that our stomach is rarely filled to capacity, so we are almost always ready to eat if the opportunity arises – if there’s food on offer and you’re thirsty but confuse it for hunger, it’s easy to say yes to eating. Staying hydrated may well help your brain to avoid this confusion!

Drinking a glass of water can be a good distraction

Very often, the factors driving us to eat are not connected to hunger. Think about the times that you snack when you know you’re not really hungry – these might be related to habit, the time of day, boredom, easy access to food, the sight or smell of food, others eating around you, the offer of food and the list goes on. In everyday life, we are rarely too full to eat more, so the thought of the pleasure of food in any one of these instances can easily lead us to snack. The wanting of food in certain situations has been shown to be a conditioned response, this means you have learned to associate eating food with these situations. Something learned can be unlearned, so pick a situation where you know you reach for food when you’re not really hungry and drink water instead! You’ll reduce your thoughts about food in those situations and unlearn the food connection.

Replace kilojoule-containing drinks with water

The most well supported evidence behind drinking water to lose weight is that the simple act of replacing kilojoule-containing beverages with water reduces your overall kilojoule intake.

We know that if you would like to lose ½-1kg of weight each week, you need to reduce your daily kilojoule intake by somewhere between 2000 and 4000 kilojoules each day. This may sound like a lot, but something as simple as changing kilojoule-containing drinks to water can quickly result in a kilojoule deficit significant enough to result in weight loss.

Try these 3 simple changes to your day:

1 glass water (instead of 1 glass (250mL) orange juice)
1 bottle unflavoured mineral water (instead of 1 small bottle (300mL) coke)
1 glass water with fresh lemon slice and ice (instead of 1 glass (150mL) white wine)

Changing these 3 drinks to water will reduce your daily kilojoule intake by around 1300kJ. This alone, is enough to set you on the path to losing a little more than ¼ of a kilogram each week. If you do some further planning to make some changes to the foods you are eating and incorporate a little physical activity, your kilojoule deficit could easily reach 2000 kilojoules or more.

If you would like the tools, motivation and support to put some changes into place, call Jenny Craig to help you take your next positive step towards healthy diet and lifestyle changes.

get started on your weight loss journey today

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