Introduction
Individuals with diabetes and health enthusiasts are constantly in search of healthy foods and snacks that do not spike blood sugar levels. This search can be quite challenging as we are constantly surrounded by a lot of options that may further confuse us. Fruits and vegetables, though generally healthy are also a lot to choose from. Grapes are one of the answers we seek. They are healthy to eat, help maintain healthy blood sugar levels and may prevent diabetic complications.
Blood sugar
Blood sugar which is also known as blood glucose is a measure of the amount of sugar in the blood. Blood sugar is produced when carbohydrate-containing foods are eaten and broken down into smaller units. When this happens, the quantity needed by the body is absorbed into the body cells and the excess is stored in the liver.
The presence of sugar in the body is important as it provides the cells with energy without which the cells cannot function properly. However, the amount of sugar in the blood should be regulated as high levels of sugar in the blood for extended periods of time may cause damage to the blood vessels.
Blood sugar regulation
As blood sugar levels increase from the consumption of carbohydrate-containing foods, a gland in the body called the pancreas produces insulin. Insulin is a hormone in the body that prompts the absorption of blood sugar into body cells for energy and the excess into the liver for storage. Conversely, a hormone called glucagon is released when the glucose level is low in the blood. This hormone stimulates the release of blood sugar from the liver back into the blood.
Blood sugar measurement
Blood sugar can be measured using a blood sugar machine before and after meals. Before a meal, stable blood sugar ranges between 70 mg/dL (3.9 mmol/L) and 100 mg/dL (5.6 mmol/L). If fasting blood glucose is 126 mg/dL (7 mmol/L) or higher on two separate tests, diabetes is diagnosed.
Diabetes
This is a chronic condition that is characterized by the inability of the body to regulate blood sugar properly. There are two types of diabetes. Type 1 and Type 2 diabetes.
Type 1 diabetes
This happens when blood sugar is high because of the body's inability to make insulin. A hormone responsible for regulating blood sugar.
Type 2 diabetes
This type of diabetes is a result of the body's inability to make enough insulin or when the insulin made by the body is not working properly.
Causes of diabetes
Diabetes is caused by a range of factors. Some factors are genetically associated while other factors are environmental and can be managed. Research has shown that diabetes can be managed by lifestyle changes, implementing healthy dietary choices and exercise. Healthy and wholesome foods have been shown to reduce the risk of diabetes and diabetic complications.
The causes of diabetes are
- The absence or reduced function of insulin
- Being overweight
- Family history of diabetes
- Asian, black African or African Caribbean origin
- High blood pressure
- Medication, such as steroids for a long time
- Gestational diabetes during pregnancy
Grapes a potential contributor to blood sugar regulation
Grapes, also known as berries, are the sweet fruit of the woody grapevine. This fruit is a people's favourite because of its sweet taste. Over the years, its content has been used to make wines and fruit snacks. Grapes have been found useful in blood sugar regulation due to their numerous polyphenol and flavonoid content which may reduce hyperglycemia and restore pancreatic beta cell function thereby providing benefits especially to type 2 diabetics. One of such polyphenols is resveratrol.
Resveratrol
This is an antioxidant that is naturally found in grapes. It has powerful antioxidant activity, potent against a range of diseases. Many studies have found it active against diabetes and its cardiovascular complications based on its antioxidant, anti-inflammatory and hypoglycemic activities. Resveratrol has been seen to:
- Exert antioxidant activity
- Improve glucose uptake and metabolism
- Enhance pancreatic beta cell function
- Improve insulin resistance
Exert antioxidant activity
Oxidative stress has been considered as one of the causes of diabetes, its complications and the pathogenesis of cardiovascular disease. Resveratrol is known to exert antioxidant activity by scavenging free radicals and activating the production of endogenous antioxidant enzymes.
Improve glucose uptake and metabolism
Normal glucose metabolism is crucial to maintain normal physiology. Diabetics however are unable to metabolize glucose properly. Resveratrol has been shown to improve the uptake of glucose in skeletal muscle cells.
Enhance pancreatic beta-cell protection
The pancreatic beta cells are endocrine cells that synthesize, store and release the hormone insulin. These cells antagonize glucagon to maintain circulating glucose levels within a narrow physiologic range. Beta cells are found in the pancreas in clusters known as islets. In type 1 diabetes, for example, the body attacks the pancreatic beta cells and destroys them. Thereby preventing the supply of insulin. Resveratrol has shown protective functions for the beta cells in the pancreas.
Improve insulin resistance
This happens when body cells do not respond easily to insulin. Insulin is a hormone responsible for prompting body cells to absorb sugar from the blood for energy. When there is insulin resistance, body cells are unable to respond to promptings from insulin thereby allowing accumulation of sugar in the blood. Resveratrol has been seen to improve insulin resistance through the activation of certain pathways.
Glycemic index of grapes
The glycemic index is a rating system for carbohydrate food and drink. It measures the rise in blood sugar in response to the consumption of food and drinks. This response can be quick, moderate or slow. The glycemic index runs from 0 to 100 using pure glucose as a reference which has a glycemic index of about 100. Foods with mean to low glycemic indexes like grapes can help keep blood sugar at even levels after eating rather than increase it. These types of foods with medium to low glycemic indexes are advised for maintaining healthy blood sugar levels.
Glycemic load of grapes
This is a measure of the amount of carbohydrates in food and its insulin demand.
Individuals with diabetes are advised to maintain a diet of foods with low glycemic load as this improves diabetes symptoms. Grapes are one of the many fruits with a mean glycemic index and a low glycemic load. It therefore can be consumed moderately by individuals with diabetes.
Grapes are also fiber rich which helps in blood sugar control. It is a good source of insoluble fiber which supports insulin sensitivity and a healthy bowel.
FAQs
What are grapes?
Grapes, also known as berries, are the sweet fruit of the woody grapevine. This fruit is a people's favourite because of its sweet taste. Over the years, it has been consumed widely and its content has been used to make wines and fruit snacks.
Do grapes help diabetes?
Research has shown that resveratrol, one of the polyphenols found in grapes, is useful in regulating blood sugar levels. It also supports the diabetic condition by Improving glucose uptake and metabolism, enhancing pancreatic beta cell function and improving insulin resistance. Grapes have also been found to be rich in fibre with a low glycemic load.
Are grapes safe for diabetic consumption since they are sweet?
Grapes are a sweet fruit. They however have a mean glycemic index and low glycemic load. This means that even though they are sweet, they do not spike up blood sugar levels and do not make demands on insulin. They are also rich in fibre and polyphenols which are very good for diabetic health.
How much grapes can I eat as an individual with diabetes?
Grapes are a superfood useful in diabetic management, however, they should be eaten in portions along with balanced meals as one of the recommended five a day to maintain good health.
Can I treat my diabetes using grapes?
Individuals with high blood sugar levels are advised to see their doctor for treatment. Neither grapes nor any other thing should replace the doctor's prescriptions. Grapes are only a healthy food or snack option for individuals concerned about their blood sugar levels
Summary
Grapes are a superfood for individuals with diabetes. It is packed with antioxidants and polyphenols that support healthy blood sugar levels. It is also rich in fibre and has a low glycemic load. All these qualities make grapes suitable as one of the recommended five a day for everyone, especially individuals with diabetes. Grapes are sweet and easy to eat, whether as snacks, food or drinks. It should be noted that grapes should be consumed in portions as with other fruits and vegetables for a balanced meal and overall wellness.
References
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