Based on the latest science, there is support for polyphenols helping to protect against diseases such as cancer, cardiovascular diseases, diabetes, and dementia (1).
This article will take a look at some low-carb foods that are high in polyphenols.
What Are Polyphenols?
Polyphenols are naturally occurring compounds found in many plants. These polyphenols are responsible for the pigment/color of the plant and/or food.
We can find polyphenols in a wide range of foods from fruits and vegetables to chocolate, spices, and even tea and wine.
For example, you can often hear the merits of red wine, dark chocolate, and various berries discussed in the media because they are polyphenol-rich foods.
All plant foods contain these compounds in varying concentrations.
However, this article will concentrate on low carb sources of polyphenols.
What Are Antioxidants?
Polyphenols are a type of antioxidant; compounds which directly help protect our cells from oxidation.
Factors such as chronic inflammation due to poor lifestyle, diet, lack of sleep, and smoking all influence our health.
As a result, free radicals can form which attack our healthy cells and cause damage to our DNA (6).
Hence antioxidants are vital. They strengthen our immune defenses and can delay or inhibit oxidative damage.
Our body naturally makes its own antioxidants, and whole food sources of antioxidants appear to be beneficial.
However, most studies testing isolated (supplement) antioxidants have found no benefit.
Let’s now take a look at 10 of the best sources of polyphenols.
Low-Carb Foods That Are High in Polyphenols
First of all, I have selected these foods from a variety of different groups.
Therefore you will see fruits, nuts, other healthy snack foods and some drinks.
One of the most antioxidant-rich foods is the blackcurrant.
Blackcurrants contain an enormous amount of polyphenols and have extensive studies showing their potential use as a therapeutic food.
In a 2014 study, a double-blind, randomized controlled trial tested the impact of blackcurrant supplementation versus a placebo.
The result was that compared to the placebo group, the blackcurrant group had decreased biomarkers of oxidative stress and improved vascular health (10).
Most noteworthy for blackcurrants is their vitamin C content. They contain well over 300% of the recommended daily amount per cup.
Blackcurrants are also a low-carb food, with one of the lowest carbohydrate contents among fruits.
Cinnamon is one of the richest foods in polyphenols.
As a spice, people usually use cinnamon to add flavor to food. Some famous foods that use cinnamon are of course pumpkin pie and mulled wine.
Cinnamon has a great deal of documented health benefits.
Particularly relevant is a meta-analysis of 10 randomized controlled trials published in 2013. This study showed that cinnamon had the following “statistically significant” benefits:
- Decreased fasting plasma glucose
- Reduced triglyceride levels
- Increased HDL-C levels and reduced LDL (11).
Therefore it’s probably a good idea to include this tasty spice in our diets.
One way I love to use cinnamon is in coffee. A homemade ‘latte’ using coffee, heavy cream, vanilla extract, and cinnamon tastes great.
3. Dark Chocolate
Dark chocolate is one of the most nutrient-dense foods on earth. It’s also one of the best sources of antioxidants.
First of all, let’s clearly separate between good chocolate and junk chocolate.
To get health benefits from chocolate, you should be eating at least 70% cacao bars – but preferably 85% or higher. These higher cacao percentage bars are low in sugar and high in nutrients.
As polyphenols and their health impacts have become more known, dark chocolate has become one of the most studied foods we have.
The data from this research is very impressive too.
One randomized study showed that dark chocolate promotes satiety, lowers the desire to eat something, and suppresses energy intake. These results were the opposite of milk chocolate (12).
Another study – a meta-analysis of randomized trials – found that dark chocolate (or cocoa) had consistent acute and chronic benefits on blood flow and blood pressure. Additionally, it also had previously unreported benefits on insulin levels (13).
Dark chocolate has an overall impressive nutrient profile, containing high amounts of most minerals such as zinc, magnesium, iron, and potassium.
Due to the caffeine, many people love coffee for an energy boost in the morning too – myself included!
Previously demonized due to a suspected role in cancer, coffee was finally removed from the World Health Organization’s list of potential carcinogens in June of 2016.
As for coffee and health; well, the list of potential benefits are just growing and growing.
Coffee has a somewhat controversial status concerning cardiovascular health. Since caffeine can raise blood pressure, some have theorized coffee may have cardiovascular risks.
A 2015 randomized placebo-controlled trial sought to address these concerns. A total of 75 participants had their health markers checked 1 hour after coffee consumption, and 8 weeks after daily consumption.
The coffee drinkers and non-coffee drinkers showed the same results in blood lipids and vascular function. There were no differences between drinking coffee and not drinking coffee.
The only difference in results was that the coffee drinkers showed an increase in plasma antioxidant capacity, whereas the placebo group did not (16).
Published in April 2016, a comprehensive review of the benefits and risks of coffee considered the drink’s safety profile.
After examining all potential concerns, the authors concluded that “the benefits of coffee clearly outweigh the risks” (17).
Coffee is a great low-carb drink – just be careful not to drink sugar-sweetened versions!
5. Red Wine
Red wine is a drink universally praised for its supposed health benefits.
Firstly, red wine is very low in carbohydrate content, so it’s okay for a low-carb diet (providing you’re not drinking bottles of the stuff!)
Also, it makes a great combination with some aged cheese, prosciutto and a few pieces of dark chocolate.
But, it does contain alcohol. And alcohol is not good for us, right?
Actually, evidence shows that alcohol can play a role in a healthy lifestyle if consumed in moderation.
However, the opposite effect comes into play in individuals consuming substantial amounts of alcohol. As a result, low to moderate consumption of alcohol may be better than either drinking regularly or not drinking at all.
Next up, nuts!
Pecans are nuts natively grown in Mexico and south-eastern areas of the United States.
They are very nutritious, containing beneficial micronutrients and are an especially good source of copper, manganese, zinc, and magnesium (23).
In addition, pecans are also a low-carb food. The carbohydrate content is only 4g (3g fiber) per ounce.
Particularly pertinent is their polyphenol content. In studies, these polyphenols exert antioxidant influences to positively impact lipid profiles (24).
Most of all, the antioxidants in pecans significantly increase the antioxidant capacity of our blood and help prevent LDL-oxidation in humans (25).
Another polyphenol-rich and (relatively) low-carb food is the blueberry.
Blueberries are one of the highest sources of antioxidants in our food and have some impressive data behind them.
Here are just four of them:
- Blueberry polyphenols (known as anthocyanins) help protect against age-related cognitive impairment (26).
- Blueberries decrease cardiovascular risk factors in obese people with metabolic syndrome (27).
- A high intake of the polyphenols found in blueberries reduces heart attack risk in young women (28).
- Berry anthocyanins seem to improve memory in the elderly. Blueberry supplementation led to better episodic memory, blood flow and visual ability (29).
One of the very best ways to eat blueberries is also one of the simplest; blueberries and heavy cream make for a great, tasty dessert.
There are also various blueberry wines, which are generally even higher in polyphenols than red wine.
8. Green Tea
Another drink full of polyphenols is green tea.
First originating in China thousands of years ago, green tea is now consumed around the world.
While green tea is very rich in polyphenols, it has almost no nutritional value. 100g contains approximately 1 calorie, and there are only minimal amounts of minerals present (30).
Results from a meta-analysis of 18 prospective cohort studies show green tea impacts on cardiovascular risk.
A dose-response analysis showed that one cup per day increases in green tea were associated with a 5% decreased CVD mortality (31).
Interestingly, green tea showed no positive impact on cancer risk in the study, but black tea did.
Perhaps some of the most impressive research behind green tea revolves around its neuroprotective benefits.
A range of well-controlled studies exist, showing how the polyphenols in green tea can positively impact – and alter – the brain-aging process (32).
Also a polyphenol-rich berry, blackberries are one of the best choices of fruit for our health.
An interesting fact that you may or may not know about the blackberry is that one ‘berry’ is not technically one fruit.
Each so-called ‘berry’ actually contains anywhere from 50 to 100 small, rounded ‘drupelets’.
Blackberries contain a wealth of beneficial compounds. Like blueberries, they do not provide a significant amount of vitamins or minerals, but they are one of the biggest dietary sources of polyphenols (33).
Similar to blueberries, the anthocyanin class of polyphenols are found in blackberries.
Finally, if you’re looking for a tasty idea on how to eat blackberries, then I recommend combining with heavy cream.
10. Black Tea
Last but not least is black tea.
Black tea comes from the same variety of plant as green tea. Unlike popular opinion, they are not entirely different species (34).
The only differences come in the processing of the leaves.
Workers pick and dry green tea immediately. On the other hand, they wait for black tea leaves to ferment in the sun before drying.
Compared to green tea, black tea has a higher amount of some antioxidants (theaflavins) and a lower amount of others (catechins) (35).
Both of these polyphenols have protective health benefits for our body.
Black tea has potential cancer-preventive effects in the body, though this needs further investigation (36).
Another study claims that clear, sufficient evidence shows reduced cardiovascular disease risk when drinking more than 3 cups of black tea per day (37).
Share this Image On Your Site With the Code Below
The most noteworthy observation about these foods is that there was a total of three fruits and vegetables.
We don’t need to be eating apples, bananas, and oranges each day to get enough antioxidants.
In fact, most of the foods that are highest in polyphenols are things that most people wouldn’t expect. Dark chocolate, coffee, and herbs and spices are a good example of this.
Eating some dark chocolate, a few cups of coffee or tea and cooking with spices are all straightforward and enjoyable things to do.
And they all go a long way in improving your health.