Are Undigested Carbs Making You Gain Weight?

The body converts carbohydrates into glucose which is its main energy source. When it lacks or has carbs in excess, fatigue, low sugar, constipation, weight gain, and diabetes may occur. When the thyroid doesn’t produce enough thyroid hormone this results in hypothyroidism, which leads to the body’s inability to produce enough gastric acid for breaking down proteins, and carbs; the main energy builder of the body. The Thyroid is a small, butterfly shaped gland at the front of the base of the neck, it controls many important systems in the body and is responsible for regulating body temperature, metabolism, your digestive system as well as controlling your appetite.


What does the body do with carbs it can’t digest?

A well-balanced ratio of carbohydrates is important for overall health, weight management and energy levels.  But, when carbohydrates are consumed in excess, and are not used, the body, through the liver, processes unused or undigested carbs it into fat for long-term storage. If a patient consumes too many carbs, or the wrong carbs and these are converted to fat due to indigestion, it can explain why most patients with hypothyroidism and thyroidectomy experience rapid weight gain. This is why low-carb, high protein diet is advisable for patients with hypothyroidism or thyroidectomy, and if possible, a nutritionist should be consulted to make sure that the proper foods are focused on.

In addition to this, low levels of stomach acid also cause nutrient deficiency, which, among other things leads to fatigue, which can further prevent patients with hypothyroidism or thyroidectomy from being as active as they once were.


Decreased activity levels, can lead to a build-up of carbs in the system which can lead to negative side effects on the body like these:

·       Weight gain: Perhaps this is the most noticeable and direct consequence of undigested carbohydrate.

·       Overgrowth of bacteria in the colon (as a result of indigestion) which in turn leads to bloating and excess gas.

·       High blood pressure: A common complaint in patients with hypothyroidism and thyroidectomy.

·       Diabetes: Excessive fat also exposes the patients to the risk of Type 2 diabetes which comes about when there is excess glucose in the blood due to insulin resistance.

·       Insulin resistance: Insulin works hard to eliminate excess sugar from the bloodstream and over time, with a constant, high demand the cells in the pancreas that produce insulin wear out.

·       Diarrhea: When the body cannot digest food properly, it tries to eliminate them. This can come out as watery stool.



Low stomach acid which can lead to nutrient deficiency, which also leads to fatigue, and potential weight gain, seems like a catch-22, but it can be managed with the proper foods and the proper intake of carbohydrates. Moderation and consuming food that contains healthy carbohydrates (complex or simple) is advisable. But, also, if you have low stomach acid you should eat smaller meals, 6 times per day instead of 3 big ones. This way you’l have enough stomach acid to digest smaller amounts of food and it will rev up your metabolism! You can also help increase your stomach acid by adding certain foods to your diet. This is discussed in depth in another article on our website. (Learn More Here)


The following foods are among the healthiest, low carb sources and are very nutritious:

1.     Fruits and vegetables

Though some fruit contains large quantities of carbs due to the presence of natural sugar, some of them are low in carbs and contain nutrients needed by the body daily.

·       Watermelon: At the top list of healthy fruits with low carbohydrate is this quintessential summer fruit that contains only about 7.55g of carbohydrate for each 100g of fruit. Its low fiber content makes it easy for the body to absorb and it is also high in vitamin A.

·       Berries: Strawberry (7.68g), blackberry (9.61g) Raspberry (5.44g), per 100g for each fruit, makes these berries stand out as a low carb option. They are also rich in vitamin C, antioxidants and potassium.

·       Cantaloupe: containing only 8.16g for each 100g, this orange melon is also very low in carb and also rich in vitamin C and potassium.

·       Other fruits include; avocado (8.53), honeydew (9.0), and peaches (9.54) per 100g.


Vegetables are another great source! Vegetables contain less carbs than fruit, are very high in fiber and are low in calories. Plus, many are a great source of much needed protein!


 Low Carb Vegetable Options

·       Cucumber: 2.16g of Carbs when peeled; and 3.63g when not peeled for every 100g.

·       Iceberg lettuce and Celery: although less nutritious than cucumber, this vegetable contains only 2.97g carbs for each 100g.

·       White mushroom Contains 3.26g of carbs per 100g

·       Spinach: For every 100g, it contains 3.62 grams for carbs and is a great source of magnesium!

·       Others include; broccoli, swiss chard, bell peppers, zucchini, cauliflower, etc.


2.     Foods

The following foods contain some the healthiest and easily accessible forms of carbs needed in the body

·       Milk: For each 100g, milk contains only 5g of carbohydrate

·       Oatmeal: with 12g per 100g, oatmeal is pretty low in carb

·       Lentils: Containing only 20.1g of carbs for each 100g, potatoes are highly recommended

·       Sweet potatoes: 23.2g for each 100 grams of rice is definitely a healthy source of carb

·       Other are; brown rice (25.6), raisins (79.2), chestnuts (53g), navy beans (26.1g), etc.



If you’re unsure what food groups or nutrients you need to focus on, your doctor can perform a test for micronutrient levels to determine what nutrients your body is deficient in. After that, you can either talk with your doctor, a nutritionist or dietician to learn what foods and carb sources are best for your body. In addition to this, patients with thyroid disease, hypothyroidism and thyroidectomy should take a good multi-vitamin that has high a bioavailability, like ThyVita. ThyVita is a patent pending nutritional supplement that has a higher bioavailability and produces results you can actually feel




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