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  • Dr Thor Conner

Berries, Food as Medicine

I write this as I am enjoying a healthy serving of fresh organic blueberries that we had the privilege of picking ourselves last weekend at Joe’s Blues Moss Funnel Farms an organic farm in Bangor, MI. Since I follow a low carb lifestyle, berries are some of the best choices of all fruits for folks on the low-carb life. Berries sport a pretty decent nutritional profile, loaded with antioxidants, fiber, vitamin C, and low in sugar, even though they tend to be sweet and delicious.

I love berries, most people do. There are so tasty and there are so many different kinds. They have been a part of our diet since way before agriculture, probably even before we were humans, as many primates rely on berries as a food source. Berries are best fresh but are also well suited to food preservation because of their high antioxidant content, which naturally preserves their nutritional content. Most of them can be fermented into wine

There are many fruits that can call themselves a berry, and there is a difference between the botanical and culinary classifications. Berries are botanically the result of a single ovum of a plant, one flower. The best example is the blueberry. Many things we don’t think of as berries actually are, like bananas and nightshades (tomatoes, peppers and eggplant) and many aren’t (strawberry is a swollen stem and raspberries are lobular fruits from many flowers). For simplicity, I want to look at culinary berries, soft fruits, and their carbohydrate load (sugar vs fiber for total net carbs) medical and nutritional benefits.

Here is a breakdown of some of the berries that we enjoy…

Blueberries are high in fiber, vitamins C and K and antioxidant polyphenols called anthocyanins that reduce oxidative stress, specifically, from LDL (bad) cholesterol, which effects the cardiovascular system.

Blueberries are helpful in managing diabetes and can improve insulin sensitivity in type 2 diabetes as well.

One cup of blueberries provides the 84 calories (about 21 carbs total or 17 net) with 3.6 grams of fiber. There is also about a quarter of the RDA for Vitamins C and K and the mineral manganese.

Raspberries. One cup of raspberries provides about 64 calories, 15 g sugar, offset with a whopping 8g of fiber, making them one of the best fruits for the carb conscious (7 net carbs). The vitamin C level is near double that of blueberries.

Raspberries contain a group of polyphenols known as ellagitannins, which can significantly reduce exercise related oxidative stress and induce an increase in leptin, a hormone that increases satiety.

Most common raspberries are the red varieties; however, black raspberries also have a number of health benefits. Black raspberries have proven to reduce risk factors for heart disease, such as blood pressure and blood cholesterol, and reduce inflammation. They even have cancer fighting properties, and have been shown to reduce the size of (pre-cancerous) polyps in the colon.

Blackberries are another high fiber berry, coming in at 8 grams per cup. That same cup has just 62 calories and 16 grams of sugar, but the high fiber reduces net carbs to just seven. Blackberries have a high antioxidant content that can be up to 5 times higher in wild harvested than cultivated berries. They have been shown in human studies to reduce LDL oxidative damage, which means they are protective for the cardiovascular system.

Strawberries are one of the most commonly consumed berries in the world and also one of the best sources of vitamin C. Studies have shown strawberries reduce inflammation by lowering serum levels of inflammatory cytokines, such as IL-1β, IL-6 and C-reactive protein (CRP). This means that strawberries are protective against heart and blood vessel disease, cholesterol and triglyceride levels and overall oxidative levels. There is even some evidence that strawberries may be effective for lowering diabetes type 2 risk.

One cup of strawberries yields just 47 calories, but are relatively high in sugar at 12 grams. Since the fiber count is only 3 grams, there is a net carb load of 8 grams, which is still low if you are counting carbs compared to non-berry fruits.


Cranberries are an extremely healthy fruit with a sour taste due to their lack of sugar and high concentrations of bioactive plant compounds. Famously, cranberries contain a compound called proanthocyanidins, may help prevent UTIs by reducing the ability of bacteria (E. coli and H pylori) to adhere to a mucus membrane causing them to be washed away.

Because of the taste, they are rarely eaten raw, at least not twice. Instead, they are commonly consumed as an ingredient, a juice (blend) or as a freeze dried powdered supplement. A cup of cranberries comes in at 46 calories, 12 g of sugar and 5 g of fiber for a net carb load of 7.

The common mistake in the application of cranberry for a UTI or bladder infection is in thinking that the juice carries the same punch as the freeze dried whole berry. All of the antioxidant punch of cranberry is in the skin and not throughout the berry, like with blueberries. That means that the juice is not sufficient for UTI treatment, so unless it is a whole berry juice that is unsweetened, use a capsule.

Grapes. Yes, grapes are considered berries.

Grapes can be consumed as whole, raw fruit or as juice, wine, raisins or vinegar. The medical benefits are provided by whole grapes, some juices, raisins, and extracts (supplements). Wine, and vinegar can have their own health benefits, but we’ll save that for a later blog.

One cup of whole, raw red seedless grapes provides about 90 calories and 24 g of sugar. Offset by 4 g of fiber, this makes the net carb load about 20, which makes them the highest for any type of berry. Nutritional data varies slightly depending on the type of grape but most grapes aren’t good for keto.

The skin and seeds of grapes are rich in polyphenols, and grape seed extracts have been shown to lower both blood pressure and heart rate. Eating grapes can be a great part of a plan to reduce cholesterol. There have even been studies showing that grape juice improved memory and driving performance.

Now here are a few less common berries with a lot of nutritional punch.

Bilberries are very similar to blueberries, and the two are often confused. Bilberries are European natives and blueberries are native to North America. Most consumption of bilberry in America is as a supplement, usually for eye health or diabetes management. Studies have shown that bilberries are effective at reducing inflammation, increase HDL and reduce LDL cholesterol and lower the risk of heart disease and metabolic syndrome.

Goji berries, also known as wolfberries, are native staple of China and have long been used in Traditional Chinese Medicine (TCM). They have recently become very popular as an import to the US and Europe, with their status as a ‘superfood’ driving the popularity.

One ounce (28 grams) of dried goji berries provides about 110 calories (28 grams of sugar) with about 4 g of fiber (24 net carbs) and are the one of the few berries (along with cloudberries) to provide protein and even some fat. Goji berries also contain copper, vitamin A and zeaxanthin, which are important for eye health, and are used to prevent degenerative conditions.

Acai bowl, a common way to enjoy Acai

Acai (ah-sigh-EE) berries grow on acai palm trees native to the Amazon, they look a bit like grapes. Like Goji berries, they came into popularity as a ‘superfood’ and are loaded with antioxidants. One hundred grams of acai berries bring 70 calories, with one carb and 2 grams of fiber, that’s NO net carbs. Acai is the best berry for Keto, but very hard to find fresh. They are readily available frozen and go great in a smoothie.

There are many health claims that have been made in the marketing of acai berries. It is true that they can contain as much as ten times the antioxidant polyphenols than blueberries, and are fantastic at increasing serum levels and reducing oxidative stress. Acai has been shown (at high doses, 200g/day/1 month) to reduce blood sugar and cholesterol levels and improve insulin response. There is some evidence that acai can improve performance in athletes, reducing ox-stress in muscles (from exercise) and improving recovery time. There is a paucity of evidence supporting claims that acai reduces blood pressure.

Some honorable mentions in the berry world. Aronia (choke) berries polyphenols will actually reduce UV damage on the skin. Elderberries contain chemicals that prevent flu viruses from infecting healthy cells. Logan Berries are a cross between raspberries and blackberries, and have more vitamin C than either parent. Lingon and Cloud berries are hard to cultivate, so they are usually wild harvested (so Nordic). Cloud berries contain a good amount of protein, no fructose (!? maybe the only fruit w/o fructose), and almost 400% of the RDA of Vitamin C, 6-8 times more than any other berry!

One concern I forgot to mention is that it is a good idea to get organic berries whenever possible. The humble strawberry is a long running #1 on the EWG's Dirty Dozen and grapes are in at #6. Most other berries are squeezed out of that list but the way berries grow means they tend to concentrate pesticides in their fruit. So go organic whenever possible to avoid unnecessary exposure, it's worth the extra cost.

I didn’t include much in the way of therapeutic doses for these because there are not standard therapeutic doses and none of them are any sort of miracle drug. Generally speaking, most of the research has been focused on cardiovascular, cholesterol, metabolic disorder (DMII) and brain health. Any plan to deal with these issues using naturopathic medicine is going to involve food and supplements, exercise, and berries and supplements made from berries should be part of a larger plan for most of what they address medically. As always we would love to help you find the path to health.

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