Raspberries in type 1 and type 2 diabetes mellitus

Among the many types of berries, raspberries are especially popular not only due to their excellent taste, but also due to their undoubted benefits. And given their low glycemic index, raspberries are very well suited for a diet aimed at stabilizing blood sugar levels.

Recent statistics show that 30.3 million people, or 9.3% of the U.S. population, have diabetes. Additionally, 347 million people worldwide currently have diabetes, and it is projected to become the seventh leading cause of death by 2030. [ 1 ]

The nutrient profile of red raspberries and their polyphenolic components (i.e. anthocyanins and ellagitannins/metabolites) make them candidates for regular inclusion in diets aimed at reducing the risk of diabetes.[ 2 ]

Benefits and harms of raspberries for diabetes

It is not for nothing that the common red raspberry (Rubus idaeus) is considered a rather watery berry, since in 100 g of fresh berries the water content reaches almost 86 g, and the amount of fiber is 6.5 g. It is clear that the calorie content is low: per 100 g - 52 kcal, which is five times lower than the same amount of white bread, and one and a half times less than boiled potatoes.

These berries contain the most potassium (152 mg/100 g), followed by phosphorus (29 mg), calcium (25 mg) and magnesium (22 mg). The iron content in 100 g does not exceed 0.7 mg; almost the same amount of manganese and slightly less zinc. There is copper (0.09 mg/100 g) and selenium (0.2 μg/100 g). Among the vitamins, the first places are occupied by ascorbic acid (26.2 g/100 g) and vitamin B4 or choline (12.3 mg/100 g). If vitamin C protects pancreatic cells from oxidative stress, then vitamin B4 not only takes part in carbohydrate metabolism, but also improves the condition of insulin-producing β-cells of the pancreas. [ 3 ]

It also contains vitamins such as alpha-tocopherol, niacin, pantothenic and folic acids, pyridoxine, thiamine, riboflavin, carotene (provitamin A) and vitamin K.

But in order for a positive answer to the question of whether raspberries can be eaten with diabetes to be as well-founded as possible and not to raise doubts, the amount of sugar should be indicated.

When nutritionists recommend raspberries as a healthy food for patients with diabetes mellitus type 1, 2 and gestational diabetes, they are guided by the fact that the glycemic index of this berry is low (25), and that 100 g of berries contain only 4.4 g of sugars. At the same time, 53% (2.34 g) is fructose, in the absorption of which insulin does not participate; 42% (1.86 g) is glucose (dextrose) and the rest is sucrose.

For comparison: the same amount of strawberries or watermelon contains about 6 g of sugar (with watermelon containing 72% fructose, and strawberries 42%); peach – 8.6 g (65% fructose); apricot – 9.3 g (7.6% fructose); orange – 9.4 g (27% fructose); blueberries – 7.3 g (49% fructose); dark grapes – 18.1 g (42%).

Obviously, these data allow us to give the correct answer to the question, does raspberry raise sugar? Compared to other carbohydrate products, raspberries are much less likely to cause an increase in blood sugar levels. Moreover, studies have shown that the consumption of these berries by patients with type 2 diabetes helps to reduce the level of glycated hemoglobin (HbA1c) in the blood and improve insulin sensitivity. As is assumed, this is the result of the effect of raspberry flavone derivatives - anthocyanins (in particular, cyanidin), which are also found in blueberries, blackberries, strawberries, cherries and dark grapes.

Now a little about other biologically active components that determine the benefits of raspberries for diabetes. The presence of plant polyphenols, tannins, derivatives of hydroxybenzoic and hydroxycinnamic acids and other compounds in its composition is valuable. Red raspberries have a unique polyphenol profile, which is characterized primarily by the content of anthocyanins and ellagitannins. Anthocyanins are flavonoid compounds and have a basic skeleton C6-C3-C6. They are responsible for the bright red color of red raspberries. Cyanidin-3-sophoroside, cyanidin-3, 5-diglucoside, cyanidin-3-(2 G -glucosylrutinoside), cyanidin-3-glucoside, cyanidin-3-rutinoside, pelargonidin-3-sophoroside, pelargonidin-3-(2 G -glucosylrutinoside), pelargonidin-3-glucoside and pelargonidin-3-rutinoside are the major anthocyanins in red raspberry.[ 4 ]

Thus, a study of the potential therapeutic capabilities of the phytoestrogen-antioxidant genistein (4,5,7-trihydroxyisoflavone), which is also present in raspberries, revealed the ability of this compound not only to reduce the formation of fat cells, but also to inhibit the transfer of glucose into them by membrane transporters (GLUT). Experiments also demonstrated a positive effect of genistein on the state of β-cells of the pancreas, which helps reduce hyperglycemia.

The proposed mechanism for reducing postprandial glucose is by limiting glucose uptake by inhibiting α-amylase and α-glucosidase activity. Red raspberry extracts were most effective in inhibiting α-amylase compared to other berry extracts.[ 5 ]

Another phenolic antioxidant found in raspberries is resveratrol (it is well known that it is found in large quantities in dark grape varieties), which has shown not only its anti-inflammatory activity, but also the ability to reduce fasting blood sugar levels and glycated hemoglobin in the blood in type 2 diabetes.

Finally, raspberries contain tiliroside, a glycoside flavonoid that preliminary research suggests may help obese diabetics by increasing the activity of the fat cell hormone adiponectin and normalizing blood glucose, insulin, and lipid levels.

Studies in diabetic animal models support in vitro data showing that 5 weeks of cyanidin-3-glucoside supplementation (0.2% of the diet) reduced fasting glucose levels and improved insulin sensitivity measured by insulin or glucose tolerance tests compared with control groups.[ 6 ] The effects on metabolic parameters were accompanied by reduced inflammatory cytokine gene expression in white adipose tissue and increased glucose regulator 4, but not adiponectin.[ 7 ]

Research data suggest that red raspberry components have biological activities that may be of clinical importance in the prevention or treatment of diabetes. In vitro and in vivo animal studies have demonstrated antioxidant, anti-inflammatory, and insulin-sensitizing effects in tissues, especially adipose tissue. These effects resulted in decreased glycemia and glycated proteins. [ 8 ] Enhanced insulin secretion by pancreatic β-cells is another important mechanism for controlling glucose levels and slowing disease progression.

Raspberries can be harmful to diabetes if there is an allergy or a disorder of uric acid metabolism - with the deposition of its salts (urates) near the joints and gout.

It is not recommended to eat raspberries in case of chronic renal failure, as well as during periods of exacerbation of inflammatory diseases of the stomach and for patients with aspirin-induced bronchial asthma (since the berries contain salicylic acid - 5 mg/100 g).

Experts warn that raspberries, which contain substances of the phytoethrogenic class, are contraindicated in cases of endometriosis or uterine fibroids, as well as in cases of oncological diseases of hormone-sensitive organs: mammary glands, uterus, ovaries.

For more information on which berries are useful for diabetes type 1 and 2, see the publication - Berries for diabetes type 1 and 2: which ones can and cannot be consumed?

If you don’t know what to replace raspberries with for diabetes, read:

• Strawberries for diabetes type 1 and 2
• Cherries and cherries for diabetes mellitus types 1 and 2
• Strawberries, lingonberries and raspberries for diabetes
• Viburnum for diabetes type 1 and 2
• Black, red and white currants for diabetes

Raspberry leaves for diabetes

Rubus idaeus leaves have been used as a remedy for centuries, for colds and fevers, heart problems and high blood pressure, intestinal disorders, anemia, menorrhagia, morning sickness during pregnancy and to ease childbirth and reduce postpartum bleeding.

Raspberry leaves contain tannins (derivatives of ellagic acid) and flavonoids, the amount of which is higher than in berries. Also included are organic carbonic, phenolic and hydroxybenzoic acids; terpenoids, glycosides, etc.

Raspberry leaf is a pharmacopoeial plant, studies have proven its safety [ 9 ] and many endocrinologists advise their patients to use raspberry leaves for type 2 diabetes and gestational diabetes [ 10 ] – to reduce hypoglycemia and insulin resistance – in the form of a herbal decoction, infusion or tea.