Dehydrated? 10 Foods and Drinks to Avoid and Why

November 28, 2022

Dehydration is one of the most common complications after bariatric surgery. Many factors contribute to this, such as reduced stomach capacity, swelling and inflammation, nausea, food intolerances, and medications. Since it is so prevalent post-op, it has become one of the main pillars of proper nutrition for recovery that most clinics and Bariatric Dietitians have come to implement and reinforce. Even though dehydration is common, it is one of the most preventable complications as well. There are several things to do to stay hydrated, but what things should you avoid as you try to rehydrate or prevent from becoming dehydrated? Let’s explore the top 10 food and drinks you should avoid or limit and why.

10 Foods And Drinks That Can Make You Dehydrated



Coffee contains caffeine, which is a natural diuretic, meaning your body will get rid of more fluid when you ingest it. Regular drip coffee contains 80-100mg of caffeine per each 8 ounces, but more concentrated coffee items like espresso can pack approximately 65mg of caffeine in a 1 ounce shot. Add additional items like flavored creamer and sugar (which can be dehydrating) and it becomes a poor choice to aid in rehydration. Decaf coffee is a great alternative to satisfy this craving.



Tea also contains caffeine. Not only is caffeine a diuretic, but it also accelerates dehydration by sending a signal to your pituitary gland to inhibit the production of the ADH hormone, which signals the kidneys to not reabsorb water. Decaf tea can replace regular, caffeinated tea and usually counts towards overall fluid intake at most clinics.


Sugary Drinks

Sugar has a similar impact on the body that salt does in terms of hydration. The body recognizes that too much sugar in the blood isn’t normal and it will make the kidneys work overtime to pull fluid from other areas to “dilute” the blood. Thus, producing more urine. Instead of soda, juice, or other sugary drinks, try sugar-free water flavorings, zero-sugar juice, lemon/lime water, or low-sugar sports drinks.



-       Alcohol is a toxin to the body, and the kidneys rapidly try to rid your blood of it by pulling water from other parts of the body to “flush” it out. This leads to an increased production of urine, thus leading to possible dehydration. Alcohol, in general, is not recommended at any time after weight loss surgery.


Asparagus and Parsley

Asparagine, an amino acid, is found in low levels in asparagus. This amino acid acts as a natural diuretic, although you would have to consume a larger amount to have any significant effect.

Parsley also acts as a natural diuretic as it inhibits reabsorption of water by the kidneys.


Protein (especially cured meats)

Although protein is essential after bariatric surgery, consuming too much when you are struggling with fluid intake can exacerbate dehydration. The kidneys must work harder to remove excess protein and nitrogen waste from metabolizing the protein. It is important to meet your protein goals, but stay mindful that too much protein can increase risk for dehydration.


Salty Snacks

Excess salt intake sends a signal to the kidneys to pull water from the body to help balance the sodium levels. This leaves your organs and other tissues like muscles short on water. Instead, opt for low-sodium options or salt-free snacks.


Highly Processed Foods and Fried Foods

Foods such as frozen meals, canned foods, fried foods, and other packaged foods usually contain a high amount of sodium to help preserve the shelf life and make the item more flavorful. As previously mentioned, a flood of sodium into the body tells the kidneys to pull water from other areas of your body, which “dries out” your organs, muscles, and other tissues. Keep these items to a minimum to help ensure proper hydration levels.


Sugary Treats

Just like sugar-laden drinks, sugary foods have the same effect on hydration. When there is too much sugar in the blood, the kidney will attempt to “normalize” the concentration of the blood and pull water to “dilute” it. Thus, there is an increase in fluid excretion. In general, choose low-sugar or sugar-free items after bariatric surgery.


Condiments such as Soy Sauce

Soy sauce is essentially salt in liquid form. Consuming soy sauce frequently or in larger amounts has the potential of increasing risk of dehydration. Moderation is key and having a glass of water close by helps to stay hydrated.

Planning meals, snacks, and drinks ahead of time go a long way in proper nutrition and in reducing your risk of dehydration. Write out your plan, shop for those items only, and if needed, set alarms or reminders throughout the day to get those fluids in! Keeping an eye on salt and sugar contents is key. This type of information is readily available on all packaged items and non-packaged items have nutritional information included on popular tracking apps or the MyPlate website. Adequate hydration, along with intentional planning, will keep your body properly hydrated and working at optimal levels!



jennifer davis


Jennifer Davis RDN, LD is a Registered and Licensed Dietitian Nutritionist. She works with bariatric patients on their diet and education for pre and post-surgery diet guidelines. She is always there for her patients at any point in their weight loss journey to answer questions regarding nutrition. She joined My Bariatric Solutions in December 2019.
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