9 Diabetes Superfoods: Fact or Fiction?
The internet is inundated with lists of diabetes “superfoods,” consumables that, if the articles are to believed, provide a simple solution to the difficult problems of diabetes management. It would be lovely to think so.
The truth tends to be a little more complex than that. And it is our job to bring you as much truth as we can.
So let’s delve into the nitty-gritty of diabetes superfoods, brush past the rumour and clickbait headlines, and see what we find.
9. Beans
The good news
Beans – black, white, navy, lima, pinto, garbanzo, soy, or kidney – are mainly advocated as a great source of protein for people with diabetes. Beans are also full of vitamin A and soluble fibre, which lowers levels of “bad” cholesterol and improves blood glucose control.
The bad news
Beans are also fairly high in carbohydrates. This doesn’t mean you shouldn’t eat them – the carbohydrates in beans are slower-acting than most, meaning they don’t cause an unmanageably rapid rise in blood glucose – but it’s worth being aware of.
The verdict
A study published in the Archives of Internal Medicine concluded that “incorporation of legumes as part of a low-GI diet improved both glycemic control and reduced calculated [coronary heart disease] risk score in type 2 [diabetes].[1]
The study was conducted because beans “have never been used specifically to lower the GI of the diet.” The results suggest that beans are a good source of protein and fibre when eaten as part of a low-carb diet.
8. Non-starchy vegetables
The good news
Everything. Non-starchy vegetables are rich in vitamin A, vitamin C, vitamin K, and soluble fibre, which improves blood glucose levels and reduces levels of “bad” cholesterol.
Studies have consistently linked non-starchy vegetables to lower risk of high blood pressure, heart disease, and cancer.
And unlike their starchy cousins, non-starchy vegetables are very low carb.
The bad news
Nothing, really. Non-starchy vegetables are the one food you really can’t go wrong with.
The verdict
Yes to non-starchy vegetables. Make friends with non-starchy vegetables. The American Diabetes Association recommends covering at least half of your plate with non-starchy vegetables.
Here’s a thorough list of non-starchy vegetables.
7. Berries
The good news
Berries are considered particularly good for people with type 2 diabetes. Why? Mainly thanks to a group of compounds called anthocyanins.
A study published in the Journal of Nutrition divided 58 participants into two groups: one group was given 160mg of anthocyanins twice a day, and the other was given a placebo. The group given the anthocyanins recorded a:
- 9 per cent reduction of low-density lipoprotein (LDL): LDL is also known, somewhat simplistically, as “bad cholesterol.” It’s the stuff people are usually referring to when they talk about cholesterol. It clogs up your arteries, increasing the risk of heart disease.
- 4 per cent increase in high-density lipoprotein (HDL): this is also known as “good cholesterol.” It clears LDL out of your arteries.
- 5 per cent reduction in fasting plasma glucose levels
- 13 per cent less insulin resistance
- 4 per cent in levels of adiponectin, which is hormone that increases insulin sensitivity[2]
On top of all that, berries are a good source of vitamin C and fibre, and they’re low-carb to boot. Hard to complain about berries, really.
The bad news
But complain we must. The only thing problem with berries is some of the research, which is “limited and inconclusive.”[3] But the signs are good.
The verdict
Berries should definitely pop up in your diet on a regular basis. They’re clearly good. It’s just difficult to say exactly how good.
Good berries include blueberries, strawberries, blackberries, raspberries, cherries, red cabbage (not a berry, but full of anthocyanins), and red grapes.
Try to incorporate berries into your breakfast or dessert. They’re a great way of making often unhealthy or carb-heavy meals into something more nutritious.
6. Citrus fruit
The good news
Citrus fruit – oranges, lemons, limes and the like – are full of vitamin C. One large orange contains all the daily vitamin C you need. Citrus fruits also balance your blood pressure.
The bad news
Citrus fruits are quite high in carbohydrates – 18.5g in a medium-size grapefruit, for example, while an orange contains about the same as a bourbon biscuit. If you’re following a low-carb diet, it’s not really advisable to have more than a single Satsuma in each meal.
The acid in citrus fruit can upset your stomach if you eat a lot of it. And that’s no fun. There’s a perception that citrus fruit damages your teeth, eroding the enamel. In fact, acidic fruits soften the enamel, making it more susceptible to damage. After about an hour it hardens again.
The verdict
Citrus fruit is a great source of vitamins, but should be eaten very sparingly by people on a low-carb diet. That said, of the 21g of carbohydrate in 180g of orange, 4g will be fibre, which lowers cholesterol and improves blood glucose control. So it’s best not to ignore citrus fruit altogether.
5. Fish
The good news
The NHS suggests eating at least two 140g portions of fish per week. At least one of these portions should be “oily.” Fish is recommended mainly for its protein and abundance of monounsaturated fat – “good” fat essentially – which improves heart health and clears out “bad” cholesterol.[4]
Fish is also a good source of vitamin D and vitamin B2. The former keeps your bones healthy, and the latter is good for your skin, eyes, red blood cells, and nervous system.
The bad news
There is some concern about the amount of mercury in fish. Consuming too much mercury has been linked to the development of brain diseases.[5] But, according to most nutritionists, the benefits outweigh the risk.
If you’re concerned about the amount of mercury in a particular kind of fish, read this page for a complete list.[6]
The verdict
Fish is a great source of protein and healthy fats, so make sure you get the recommended amount. But it might be best not to go too far over that amount.
4. Cinnamon
The good news
Some studies suggest that cinnamon is excellent for people with diabetes, lowering blood glucose, reducing “bad” cholesterol, and increasing insulin sensitivity. [7] [8] [9] It’s also inexpensive, making it a very practical option.
The bad news
The studies aren’t conclusive, with some concluding that cinnamon doesn’t help blood glucose levels at all.[10]
Excessive amounts of cinnamon have also been linked to liver damage in some people.[11]
The verdict
Potentially very good indeed, but the evidence is inconclusive. And, based on its links to liver damage – admittedly, also inconclusive – it might be best to wait for some more substantial evidence. But it clearly has some positive effects.
3. Oatmeal
The good news
Oatmeal is low on the glycemic index, which measures the effects of different foods on blood glucose levels. It also reduces “bad” cholesterol.
The bad news
Oatmeal isn’t particularly low-carb.[12] But it’s not bad, particularly when you compare it to other breakfast options. Starchier options like toast or croissants will not only contain more carbohydrates, but less nutrition.
The verdict
There are different kinds of oatmeal, and they all have different effects. Avoid processed oatmeal, which can usually be detected by its ranking on the glycemic index; processed foods tend to be higher. “Natural” oatmeal will also contain more soluble fibre, which is great for managing blood glucose levels.
2. Greek yoghurt
The good news
Last year, there were a number of studies that suggested Greek yoghurt reduces the risk of type 2 diabetes.[13] [14]There’s some truth to this – Greek yoghurt is low-carbohydrate, high-protein, and low in sugar – but some of the reporting went a bit overboard.
The bad news
Go for the full fat option. It will make you feel full for much longer.
That might sound strange. Surely going for the option with more saturated fat will increase the risk of heart disease.
Well, not necessarily. Fat’s more complex than that.
A lot of source suggest that saturated fat increases your risk of blocked arteries and heart disease, a complication to which people with diabetes are already prone.[15] [16] [17] But then lots of studies say it doesn’t.[18] [19] It’s a complex debate. One so fierce and long-running that it has its own Wikipedia page.
This is because there are different kinds of saturated fat, which is why the distinction of cholesterol into “good” and “bad” is a bit simplistic. Small, dense low-density lipoprotein (LDL) cholesterol particles are linked to heart disease. Bigger particles aren’t. Some studies suggest they may even protect your heart. So some foods have “healthy” saturated fat, and “good” LDL cholesterol.
Greek yoghurt is one of them. By eating the full-fat version, you reduce your risk of heart disease – or at least, you don’t make it any worse – and feel full for longer.
Read more about the – admittedly, very complicated – subject of cholesterol and fat here.[20]
Greek yoghurt is only bad for you if you eat too much of it. Just in terms of calories. But you’d have to eat more than 1000g of full-fat Greek yoghurt to get the same amount of calories as you’d find a Big Mac meal.[21] [22] So it’s not really much of a concern.
The verdict
In short, Greek yoghurt is good for people with diabetes. Especially the full-fat version. Greek yoghurt’s a great option for breakfast. Like oatmeal, yoghurt can be a great option for an often carbohydrate-heavy meal.
Nutritional values of yoghurt vary considerably depending on the brand, so it’s tricky to give a comprehensive verdict. Read the label.
1. Nuts
The good news
Most nuts are pretty good for people with diabetes. But it depends on the kind of nut:
- Almonds contain a lot of nutrients, particularly vitamin E
- Walnuts contain healthy omega-3 fatty acids
- Cashews boast a lot of magnesium
- Almonds, peanuts, and pistachios all reduce “bad” cholesterol
A study published in the Journal of the American College of Nutrition found that “nut consumption was associated with a decreased prevalence of selected risk factors for cardiovascular disease, type 2 diabetes, and [metabolic syndrome].”[23]
The bad news
Nuts tend to be high in calories. And the salted ones aren’t particularly good for people with diabetes.
The verdict
Nuts are good for people with diabetes, but their calorific qualities means they should be consumed in small amounts. And stay well away from the salted varieties.
Sources:
[1] https://archinte.jamanetwork.com/article.aspx?articleid=1384247
[2] https://jn.nutrition.org/content/early/2015/02/04/jn.114.205674.abstract
[3] https://www.ncbi.nlm.nih.gov/pubmed/24257723
[4] Fat can be confusing – which ones are good, which ones are bad. As a general rule, monounsaturated and polyunsaturated fats are “good” fats, whereas we’re advised to steer clear of saturated fat and trans fat. But even that’s debatable. Learn more about the different kinds of fat.
[5] https://www.sciencedirect.com/science/article/pii/S0031395507000338
[6] https://www.nrdc.org/health/effects/mercury/guide.asp
[7] https://www.ncbi.nlm.nih.gov/pubmed/21480806
[8] https://www.annfammed.org/content/11/5/452.long
[9] Agricultural Research Magazine; Cinnamon Extracts Boost Insulin Sensitivity; Anderson, R. et al.; July 2000.
[10] https://care.diabetesjournals.org/content/31/1/41.full
[11] https://pubs.acs.org/doi/abs/10.1021/jf4005862
[12] https://ndb.nal.usda.gov/ndb/foods/show/1892?fgcd=&manu=&lfacet=&format=&count=&max=35&offset=&sort=&qlookup=08123
[13] https://www.hsph.harvard.edu/news/hsph-in-the-news/yogurt-may-reduce-type-2-diabetes-risk/
[14] https://www.cam.ac.uk/research/news/yoghurt-cuts-risk-of-type-2-diabetes
[15] https://www.foodandnutritionresearch.net/index.php/fnr/article/view/25145
[16]https://onlinelibrary.wiley.com/doi/10.1002/14651858.CD002137.pub2/abstract;jsessionid=32FEB358A6DF0C6D7B091B08EBC2A150.f04t01
[17] https://ajcn.nutrition.org/content/89/5/1425
[18] https://annals.org/article.aspx?articleid=1846638
[19] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2824152/
[20] https://chriskresser.com/the-most-important-thing-you-probably-dont-know-about-cholesterol
[21] https://www.myfitnesspal.com/food/calories/fage-total-classic-greek-yogurt-full-fat-143214642
[22] https://www.sparkpeople.com/calories-in.asp?food=big+mac+meal
[23] https://www.ncbi.nlm.nih.gov/pubmed/22331685
