Gastroparesis is a condition where the contents of the stomach take longer than normal to empty after a meal. As a result, people with gastroparesis normally have a feeling of excessive fullness nausea, acid reflux, and heartburn.
Typically, the cause is unknown, referred to as idiopathic gastoparesis. But in cases where the cause is known, the most common cause is Type 1 or 2 diabetes.
To be clear, uncontrolled blood glucose alters how quickly the stomach empties. In fact, even in healthy people, blood glucose controls the rate of gastric emptying. This is just how our gut helps regulate blood glucose levels.
But people with chronically high blood glucose levels have a double hit coming. Let’s take a look at how gastric emptying controls blood glucose levels, why hyperglycemia is a cause of gastroparesis, and what we can do to speed things up.
Dysregulated blood glucose as a cause of gastroparesis
When we eat, our food moves from our mouth to our stomach where the first major step of digestion occurs. In a healthy person, food typically sits in the stomach for 3 hours as stomach acid and pummeling help break down protein into smaller amino acid chains.
The content and size of our meal regulates gastric emptying time. Once digested, chemosensors in our stomach signify it’s time to empty. From there, food enters into the duodenum. Stretching of the duodenum cause the stomach to stop emptying.
Another important factor that puts the breaks on gastric emptying is our blood glucose levels. As our food moves into the duodenum, the breakdown of carbohydrates into glucose and absorption into the bloodstream raise blood glucose levels.
When our blood glucose levels rise to hyperglycemia, gastric emptying is slowed to prevent it from getting worse. Conversely, during hypoglycemia, when blood glucose levels drop, gastric emptying increases to raise blood glucose levels.
This helps keep our blood glucose levels in balance. Overall, estimates indicate that the rate of gastric emptying regulates about 35% of the variation in post-meal blood glucose levels.
Another important factor is the secretion of incretin hormones by the gut. These hormones increase the amount of insulin secreted during and after a meal, and are stimulated by stretch in the gut.
Some incretin hormones, such as glucagon-like peptide-1(GLP-1), slow gastric emptying. They also inhibit glucagon release, both of which decrease blood glucose levels.
Due to problems with insulin signaling, people with Type 1 and 2 diabetes experience elevations in blood glucose levels that delay gastric emptying well beyond what is normal. Furthermore, even in healthy people, a large meal high in carbohydrate delays gastric emptying and promotes a feeling of fullness.
Nerve damage-The second hit in people with Type 1 and 2 diabetes
Whether you have diabetes or not, acute hyperglycemia will delay gastric emptying significantly. However, it’s much, much worse for those with chronic hyperglycemia such as Type 2 diabetics.
Chronically elevated blood glucose damages enteric nerves. Enteric nerves make up the enteric nervous system, the resident nervous system in our gut. These nerves play the starring role in sensing when food enters our gut as well as contraction of the smooth muscle that causes motility.
During diabetic enteric neuropathy, the gut can’t sense contents properly, delaying gastric emptying. In addition, impairment in incretin hormone secretion causes an elevation of blood glucose that slows gastric emptying further.
Overall, addressing hyperglycemia is a critically important factor for improving gastroparesis.
Addressing hyperglycemia, the most common cause of gastroparesis
As you can tell, properly managed blood glucose is a must for people with gastroparesis. One option is to eat a lower carbohydrate diet.
Since carbohydrates contribute the most to blood glucose levels, decreasing carbohydrate is a useful tactic to manage post meal blood glucose elevations.
While some people do well on a lower carbohydrate diet, many don’t stick long term. Another problem is that restricting carbohydrates below 100g/day can make you more intolerant to them. So a low carbohydrate diet is only a good option if you stay that way.
But if you like consuming carbohydrates, getting more physical activity and implementing an integrative exercise program can do wonders for managing blood glucose. This works both acutely and chronically due to adaptations from regular exercise. This includes:
- Emptying glycogen stores so there’s space for excess glucose
- Decreasing bodyfat stores, so that any excess gets stored as fat
- Increasing glycogen storage capacity in muscle
- Improving incretin hormone signaling
The best way to attack this is to get adequate physical activity in the form of walking, additional low level cardiovascular exercise, strength train 3-4x/week, and add in some high intensity interval training for good measure.
For most people with no training history, especially those with Type 2 diabetes, the vast majority of your program should be walking and strength training. Additionally, it’s a good idea to find a balance between carbohydrate intake and activity levels.
If you want to eat a higher carbohydrate diet, it’s essential to perform some amount of moderate to vigorous physical activity every week. Carbohydrates fuel intense exercise, and regular participation in higher intensity exercise is essential to managing blood glucose in high carb diets.
Good blood glucose regulation is essential to timely gastric emptying. Gastric emptying plays an important role in the proper regulation of blood glucose levels. When blood glucose gets too high, this causes delayed gastric emptying to prevent it from going higher.
Chronically elevated blood glucose levels also damage the enteric nerves that sense contents of the stomach and cause muscles of the stomach to contract. As a result, people with poorly controlled diabetes experience excessive fullness, nausea, and heartburn following meals.
Poorly controlled blood glucose levels are an important cause of gastroparesis. Since this is simply part and parcel with how our body regulates blood glucose levels, people with poorly controlled glucose must correct it to correct gastroparesis.
Circumventing this process would cause even more damage due to dangerously high blood glucose levels. Managing blood glucose levels with a low carbohydrate diet may be useful for short term improvements in this process.
Increasing physical activity and implementing an exercise program are other, longer term options as well. Ultimately, balancing both options is the key to help reverse the most common known cause of gastroparesis.