【Fan Zhihong registered nutritionist original content Welcome to forward】
Some people wonder why I like to use raisins in my recipes, especially black raisins. Someone asked: Aren't raisins sugar? What nutritional value does it have? After drying, does it still have antioxidant activity?
The raisin does contain a lot of sugar because it concentrates the sugar in the grapes. However, raisins ≠ sugar.
Raisins belong to dried fruits. Not included in the restrictions on added sugars. In national dietary guidelines, it is grouped with fresh fruit. Of course, because of the different moisture content, one pound of dry goods of raisins is equivalent to three or four pounds of grapes, so it needs to be converted.
The so-called dried fruits refer to products made from dried fruits and without adding any sugar or fat during the production process. Such as raisins, dates, dried apricots, dried figs, dried prunes, persimmon cakes, dried cinnamon and so on. They are part of the traditional diet and can be eaten directly as a snack or cooked with grains as a healthy alternative to refined sugar, candy, snacks.
Although drying treatment loses vitamin C, it does not lose minerals and dietary fiber. After the moisture is removed, minerals such as potassium, magnesium, iron, oligosaccharides, pectin and cellulose, and most of the antioxidants in the fruit are concentrated.
As a representative of dried fruit, the truth about the health of raisins should really be understood. (Friends who are impatient, please look directly at the title and the weighted part.) ）
One of the health truths about raisins: a good source of antioxidants, minerals and dietary fiber.
The grapes themselves are rich in polyphenols, which are partially lost during the drying process, but most of them can still be retained in the raisins. Because eating grapes usually spits out the skins of grapes, and raisins are eaten with skins, eating raisins can get the nutrients in the peel, including a lot of pectin and fiber in the skin, including more polyphenol antioxidants than in fruit juice.
Studies have found that among the common dried fruits, the polyphenol content in raisins is the highest grade. By weight, it is more than dried black plum and dried apricots, and more than most fresh fruits. The polyphenols in raisins include a variety of phenolic acids, flavonoids (quercetin, phenantol and rutin), and anthocyanins. In general, the higher the content of polyphenols, the stronger the antioxidant effect.
Oxygen Radical Absorption Capacity (ORAC) determination data from the USDA database show that the total ORAC in seedless raisins is 3037 μmol TE/100 g, higher than the skinned Fuji apple (2589 μmol TE/100 g), raw broccoli (1352 μmol TE/100 g), and red tomato (367 μmol TE/100 g).
Seedless raisins are lighter in color and have such antioxidant power. There is no data on dark raisins in the database, but in theory, dark raisins such as red and black will have better antioxidant properties, because some anthocyanins are retained (if you can see black, it means that most of the anthocyanins are not lost, otherwise it will fade).
The potassium content in raisins is quite abundant. The potassium content in 100 g of raisins exceeds 700 mg. An adult's daily reference intake of potassium is 2,000 mg, and eating a small handful of 25 grams of raisins can supply more than 180 mg of potassium, equivalent to 9% of the reference value. As a snack to eat in small amounts, this is excellent.
Even raisins eaten on the skin are a good source of dietary fiber. The dietary fiber content in 100 grams of raisins is 3.3 to 4.5 grams, which is 6 to 9 times that of refined white rice. During the production of raisins, some of these sucroses and fructose form fructooligosaccharides up to 8% (Olmo-Cunillera A, 2020). Fructooligosaccharides are sweet, but the human body cannot digest and absorb it in the small intestine, but it can be fermented in the large intestine, which belongs to the prebiotics that can adjust the intestinal flora, and is considered to be a generalized dietary fiber.
Compared with light-colored raisins, dark varieties not only have more antioxidant substances, but also have higher content of dietary fiber and iron. Therefore, I often recommend using black raisins in nutritional recipes.
The health truth of raisins is two: in the GI food, do not hurt blood sugar.
Raisins themselves are a medium to low GI food. According to the results of the national measurement, the GI value of raisin products is between 49 and 69 (Olmo-Cunillera A, 2020). Replacing some staple foods such as rice with raisins does not cause a more increase in blood sugar. Studies have found that eating raisins 3 times a week is associated with a lower risk of diabetes compared to drinking juice 3 times a week.
Researchers have asked overweight obese and diabetics to eat a pack of 28 grams of dark raisins (total 84 grams, about 270 kcal calories) before meals 3 times a day, replacing traditional snacks (cookies and cookies, etc., containing 300 kcal calories). After 12 weeks, there was no difference in insulin levels between the two groups, but both glycosylated hemoglobin levels and postprandial blood glucose levels in the raisin group were significantly reduced, indicating increased insulin sensitivity. Analysis of data from patients with diabetes showed a significant decrease in postprandial glycemic response in the raisin group, as well as a decreasing trend in fasting blood glucose and HbA1c (Anderson et al, 2014). Experiments conducted in healthy people found that replacing half of white rice with raisins containing 25 grams of carbohydrates did not increase the postprandial blood glucose response, and the peak blood glucose concentration and blood glucose fluctuation range were comparable to rice (Zhu et al, 2018).
The health truth of raisins is the third: it is beneficial for blood pressure and blood lipids.
Because raisins are a good source of potassium, magnesium and many antioxidants, and are also rich in oligosaccharides and pectin, eating in moderation is good for heart health. The survey found that eating at least 160 grams of raisins per week resulted in a significant reduction in the risk of high blood pressure (Borgi L, 2016).
Studies have shown that replacing snacks such as cookie cakes with raisins is more conducive to controlling blood pressure. A 12-week dietary intervention in 46 patients with prehypertension provided raisins (containing 220 mg of potassium) three times a day. Blood pressure was measured at weeks 4, 8, and 12 and it was found that systolic blood pressure was reduced by 4.8% to 7.2% and diastolic blood pressure by 2.5% to 6.4% in the raisin group (Bay et al,2012). In another study, 34 subjects ate 160 grams of raisins per day for 6 weeks, with or without daily walking exercise, and total cholesterol decreased significantly compared to not eating, as well as low-density lipoprotein cholesterol (LDL-c) (Puglisi MJ, 2009).
The health truth of raisins is number four: reasonable consumption does not lead to obesity.
Some surveys have found that people who consume more than 20g of dried mixed fruits per day have higher calorie intake and significantly lower average weight, BMI and waist circumference than those who consume less dried fruits. After eliminating various confounding factors, it was found that people who consumed more dried fruits had higher intake of vitamins and minerals and richer dietary fiber than those who did not eat dried fruits, while the number and proportion of overweight, obesity and abdominal obesity were lower (Keast D R, 2011).
After the additional intake of dried fruits, the calories are high, and the carbohydrate energy supply ratio is also high, so why is it not easy to gain weight? This may be because after eating sweet dried fruit, you no longer want to eat snack cookies and desserts. Compared with these foods, dried fruits have a higher nutrient density and more health components. Just as surveys found that people who eat nuts in moderation as a snack are not fatter than people who don't eat nuts.
The health truth about raisins number five: not as harmful to teeth as sweets.
Dental studies have found that eating a handful of raisins a day under the premise of normal brushing and rinsing does not damage teeth as much as eating sweets. Raisins contain very little sucrose, fructose and glucose adhere to the surface of the teeth for a short time, and the antioxidant components in it have a slight antibacterial effect, so the pH of the tooth surface after eating raisins does not drop much, and it does not reach the degree of damage to tooth enamel.
Of course, each kind of food has its own reasonable share, if you eat too much dried fruit, and do not replace other carb foods, or other foods to eat less, only eat a lot of raisins, it is also not conducive to nutritional balance, the same will be fat or harmful to health. I think it can be said that leaving the big premise of nutritional balance, talking about calories, talking about carbs, talking about fat, deifying a certain natural food, or demonizing a certain natural food, is a hooligan...
How many raisins are better to eat? According to the number in the literature, eating 160 grams per week has a health effect, and the average is 23 grams per day. If you can eat enough fruit to eat 200 grams per day, then you can eat it in the amount of about 25 grams. If you eat less fruit every day, you can increase it and eat 30 to 40 grams. Of course, this quantity includes a variety of dried fruits, not just raisins. Dates, dried apricots, dried figs, dried blueberries, persimmon cakes, dried goji berries, etc. are also included.
Regarding healthy eating dried fruit, you may also want to know:
Dried fruits are sweeter than fruits, can blood sugar control people eat them? How much is appropriate to eat?
Concentrated dry goods are the essence? Dietitian reminds: these dried fruits must be eaten in limited quantities!
Answers to three questions about dried fruit cooking
bibliography:
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Fan Zhihong
He is a scientist at the Beijing Food Nutrition and Human Health High-tech Innovation Center
Director of the Chinese Nutrition Society
Director of China Association for Health Promotion and Health Education
The China Association for Science and Technology employs chief experts in nutrition science communication
Ph.D. in Food Science, China Agricultural University