Last Updated on March 4, 2022 by Dr Sharon Baisil MD
Grapes have been under intense scrutiny due to their potential health benefits and risks in diabetes. What are the true health benefits of grapes? How do they work in diabetes care management? And why are some recent studies warning us about them? This article explores what’s said on both sides, so you can make an informed decision about whether or not grapes are good for diabetics.
Do grapes raise blood sugar levels?
Grapes contain a type of sugar called glucose, which is the body’s preferred energy source. The majority of the grapes’ carb content is in the form of starch. This means that when you eat grapes, your digestive system starts to break down this complex starch into simple sugars with enzymes from your saliva and stomach acid. Once the sugar molecules enter your blood, your body releases insulin to help carry them into cells throughout your body. Grapes raise both fast and slow blood sugar levels.
Slow Blood Sugar Levels: The starch in grapes is made of long chains of glucose molecules, which take a long time for our bodies to break down. This means that the carbohydrates in grapes are slowly absorbed into our blood, which can be helpful for diabetics.
Fast Blood Sugar Levels: The glucose molecules in the grape juice are already separated from their starch chains, which means they’re ready to enter the blood more quickly (pre-digested). These glucose molecules get absorbed quickly and can raise blood sugar levels very quickly.
On the other hand, Grapes do not cause blood glucose levels to go up when taken in moderation. The glycemic index of grapes is toward the lower end, which means moderate consumption does not affect blood glucose levels. The glycemic index of black grapes is 59, whereas red grapes have a GI value of 50, which is in the “low GI” category. Other fresh fruits with a low GI are blueberries, strawberries, guava, avocado, and pears.
So are grapes good for diabetics?
Grapes are not “bad” for diabetics, but their consumption should be moderate to avoid negative blood sugar levels. Eating too many grapes can cause big fluctuations in insulin levels throughout the day, which could lead to swings in blood glucose levels. Although grapes are not bad for diabetics, there are some risks associated with the consumption of grapes that need to be considered.
A study published in the British Journal of Nutrition found that moderate red grapes consumption helped reduce insulin resistance. This is one of the most important factors in diabetes care management because it helps your body use insulin more efficiently, which reduces the risk of developing heart disease and other serious health complications associated with diabetes.
How many grapes can a diabetic eat a day?
As with all foods in diabetes, moderation is the key. Diabetics should only consume 150-200 grams of grapes per day because this amount will not give you high or low blood sugar levels.
Grape juice should be avoided in individuals with diabetes. Although fruit juice has the same nutrients as grapes, it does not have the dietary fiber that aids in slowing down digestion, and this implies that grape juice may rapidly elevate blood sugar levels.
Grapes contain a good amount of potassium and vitamin K, which help reduce blood pressure and strengthen bone mass (respectively).
Grapes are packed with antioxidants. A study conducted at the University of California found that grape phenolics (a type of antioxidant) inhibited the oxidation of LDL (“bad”) cholesterol. This means that grapes may be a great way to help protect against heart disease.
Eating grapes can provide various health benefits, including lowering your risk for developing diabetes and other serious conditions associated with blood sugar spikes. The key is to eat them in moderation because consuming too many grapes can
9 Health Benefits of Grapes in Diabetes
Eating grapes can provide various health benefits, including lowering your risk for developing diabetes and other serious conditions associated with high blood glucose levels. Here are the nine potential benefits of grapes for individuals with diabetes.
Benefit #1 Prevent hyperlipidemia and heart diseases
Grapes are packed with antioxidants (including anthocyanins), phenolic acids, flavanols, and stilbenes. These potent plant compounds help to kill free radicals in the body that damage cells and lead to chronic diseases like heart disease.
Red grapes may help reduce LDL (“bad”) cholesterol oxidation, which may help protect against heart disease.
A study published in the journal Nutrition Research found that postmenopausal women who consumed grapes had better lipid profiles than those who did not. Grapes are well known for their heart-boosting benefits, but this is one of the first studies linking them with improved lipid profiles.
Moreover, researchers from the Harvard School of Public Health found that women who ate one-and-a-half servings of grapes or raisins every week had a 41 percent lower risk of heart disease than those who rarely or never consumed them.
Grape seed extract contains powerful antioxidants that protect blood vessels and stop the formation of plaque deposits in the arteries, reducing cholesterol levels and blood pressure and preventing the hardening of the arteries. Thus, grape seed extract is used to treat angina (chest pain), varicose veins, high blood pressure, and poor circulation (peripheral arterial disease).
Benefit #2 Maintain healthy blood pressure
Grapes contain potassium, which helps to reduce high blood pressure and prevent cardiovascular diseases like stroke.
A study conducted by the American Diabetes Association (ADA) found that drinking black grape juice helped lower blood pressure and improved vascular health. The researchers believe that it may be due to the grape’s high flavonoid content.
Another study published in the American Journal of Clinical Nutrition found that individuals who consumed grapes had lower blood pressure than those who did not. They concluded a significant association between grapes and reduced cardiovascular risk.
Benefit #3 Enhance bone health
Eating grapes can also help to strengthen bone mass because they are rich in vitamin K, which helps with calcium absorption. This, in turn, prevents the deterioration of bones that often accompanies aging.
A study published in the journal Carcinogenesis found that grape seed extract inhibited the proliferation of osteoclasts, which are cells that break down bone. These findings suggest that grapes may help promote bone health by inhibiting the breakdown of bones.
Another study published in the American Journal of Clinical Nutrition found that individuals who consumed grapes had higher levels of vitamin K than those who did not. Grapes are high in calcium, vitamin C, and magnesium, all essential nutrients that play important roles in keeping bones strong.
Benefit #4 Assist with weight management
Grapes contain fiber, which is beneficial for weight loss in obesity because it helps fill you up (which can curb appetite). Grapes also help to reduce the glycemic index of other foods.
A study published in the Journal of Nutritional Biochemistry found that obese individuals who consumed grapes lost more weight than those who did not. The grape intake helped reduce waist circumference, LDL cholesterol levels, triglycerides, and glucose intolerance (an early sign of diabetes).
Another study published in the American Journal of Clinical Nutrition found that individuals who consumed grapes had lower body mass index (BMI) levels than those who did not.
Benefit #5 Boost Memory and can prevent Alzheimer’s Disease
Grapes are rich in resveratrol, an antioxidant that can help improve memory and learning ability, prevent blood clots in the brain and protect against Alzheimer’s disease.
A study published in “PLOS ONE” found that resveratrol blocked a protein known as p38 MAPK, which is linked to inflammation in the brain, thereby preventing amyloid-beta from being able to damage healthy nerve cells.
Another study published in the “Journal of Alzheimer’s Disease” found that resveratrol prevented memory impairment and plaque deposition in mice injected with amyloid-beta due to its antioxidant properties.
Benefit #6 Reduce nerve damages
Grapes contain vitamin B1 (thiamine), an essential nutrient for nerve health. Nerves are cells that carry messages to and from the brain.
A study published in the journal Nutritional Neuroscience found that thiamine (vitamin B1) reduced nerve damage caused by oxidative stress. Grapes contain many other nutrients like vitamin A, vitamin C, pantothenic acid, folate, niacin, vitamin B6, copper, and manganese which also protect against nerve damage.
Benefit #7 Enhance skin health
Grapes can help improve skin quality because they are rich in resveratrol and ellagic acid, two antioxidants that prevent oxidative stress and skin aging.
A study published in the journal Photochemistry and Photobiology found that grape extracts prevented skin damage in mice. Another study published in the journal Clinical and Experimental Dermatology found that resveratrol helped reduce wrinkles and improve hydration when applied topically.
Regular consumption of grapes can help to reduce skin damage, thereby preventing age spots. The grape seed extract has also been found to prevent UVB-induced inflammation.
Benefit #8 Prevent Cancer
Grapes contain several antioxidants, including gallic acid, catechin, polyphenols, quercetin, and epicatechin, which work against the development of cancerous cells. Gallic acid is found mainly in the skin of red grapes, while catechin and epicatechin are found in the seeds.
A study published in the journal Carcinogenesis found that grapes can significantly reduce oxidative stress (which is linked to cancer growth) and inhibit the development of prostate, breast, liver, lung, and colon cancers.
Another study published in Nutrition Research found that proanthocyanidins (PACs) in grapes could inhibit the growth of all non-small cell lung cancer cells tested. PACs are antioxidants found in red wine, grape seeds, and grape skin extract.
Benefit #9 Relieve arthritis symptoms
Grapes contain vitamin K, an essential nutrient for cartilage formation prevents cartilage damage from oxidative stress and has anti-inflammatory action.
A study published in the journal Nutrition found that individuals who consumed a grape supplement for two weeks had lower levels of inflammatory markers than those who did not, suggesting that grapes can relieve arthritis symptoms.
Regular consumption of grapes helps to reduce joint pain caused by oxidative stress and inflammation due to their rich vitamin K content. Grapes are also believed to help joint repair by preventing cartilage degradation.
What are the Potential Risks of eating Grapes in Diabetes?
Risk #1 High in sulfites
Sulfites are chemicals that can produce an allergic reaction in some people who have asthma or sulfite intolerance. Dried grapes contain sulfur dioxide, which is used as a preservative for improving shelf life, but fresh grapes do not typically contain harmful levels of this substance.
Risk #2 May contain toxic pesticide residues
Grapes are grown on vines, which are attacked by vine borers and other types of pests. Farmers use pesticides to protect their crops from these attacks because grapes are used for wine production.
It is safer to buy organic grapes because they are grown without chemical pesticides.
Risk #3 Causes gastric irritation
Grapes, in general, are considered to be safe for people with diabetes because they contain low levels of carb. However, grapes can cause gastric irritation because of their high acidity.
This could lead to stomach ulcers or diarrhea if eaten in excess. The presence of seeds in grapes increases the risk factors even further by causing pain and bloating.
Risk #4 Allergies
Allergies are the most common side effect of grapes. Allergic reactions can be very serious and even fatal, so diabetics need to take care of their diet.
An allergic reaction to grapes causes a spike in histamine levels, which causes runny nose, hives, and difficulty breathing within minutes after eating them.
Grapes are also known to cause anaphylaxis, although this is very rare.
Risk #5 May contain salmonella bacteria
Salmonella bacteria can be found in grapes that have been stored at low temperatures for too long, which allows the bacteria to multiply. This only occurs when proper storage conditions aren’t met.
Frequently Asked Questions
Which color grapes are best for diabetics?
Answer: Red grapes are considered to be more beneficial for diabetics. The color of a grape does not affect its antioxidant content, but it can change the degree to which they benefit people managing diabetes.
A recent study on the effects of grapes on blood glucose control showed that eating red grapes is more effective in improving the body’s sugar control than eating green grapes.
Red grapes are also widely available throughout the year, thus making them a good option for diabetics all year long. Green grapes are only available when in season and can be expensive at other times of the year.
Do grapes spike insulin?
Answer: Yes. Grapes do spike insulin, but so do many other fruits and vegetables.
The glycemic index is a measure of how much a food increases blood sugar levels. Foods that have a high glycemic index are those that cause a rapid increase in blood sugar levels. Foods that have a low glycemic index are those that cause a slow, gradual increase in blood sugar levels. The glycemic load is determined by multiplying the glycemic index by the amount of carbohydrate in the food.
Grapes have a glycemic index of 59 and a glycemic load of 16, which means they are considered to be a high-glycemic-load food. This means they can cause a rapid rise in blood sugar levels, if taken without moderation.
Are Frozen grapes good for diabetics?
Answer: Yes, frozen grapes are a good snack option for diabetics. They are low in calories and carbohydrate, and provide a good source of antioxidants and vitamins. However, it is important to remember that all foods should be taken in moderation, and diabetics should speak with their doctor before making any changes to their diet.
Are grapes good for lowering blood sugar?
Answer: Yes, grapes are a good fruit to lower blood sugar because they contain the antioxidant resveratrol, as well as the flavonoid quercetin. These antioxidants help improve insulin sensitivity and reduce inflammation, which are both important factors in maintaining healthy blood sugar levels. Additionally, grapes are a good source of fiber, which helps slow the absorption of sugar into the bloodstream.
References
https://www.cdc.gov/diabetes/managing/eat-well/meal-plan-method.html
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5388466/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5537788/
https://www.diabetes.org/healthy-living/recipes-nutrition/eating-well/fruit
https://academic.oup.com/ajcn/article/106/2/519/4557618
https://medlineplus.gov/herbalmedicine.html
https://journals.plos.org/plosmedicine/article
https://www.uofmhealth.org/health-library/aa15456
