The term “superfood” is rapidly becoming a bit of a misnomer, particularly in the context that many people use it. If you peruse the “health food” aisle of most any supermarket of a local supplement store, you’ll notice a myriad of products that claim to contain the “best superfoods” (and therefore enhance your longevity and overall health).
Naturally, this begs the question: “What is a ‘superfood’ or ‘functional food?’”
In the technical sense, “superfood” has no concrete definition, nor are there any sort of prerequisites agreed upon by public health organizations that would characterize certain foods as being “superfoods”.
Basically, if someone says a food is a “superfood” they are trying to get across that it’s dense in nutrients (particularly micronutrients and polyphenols) that many foods are lacking these days.
In reality, the phenomenon of functional foods and superfoods is a way to describe what our natural food supply used to be. Modern agriculture processes and pesticide use are slowly but surely draining the vital micronutrients from things like fruit and vegetables.
But it’s not all doom and gloom, as you can still find a bounty of beneficial nutrients in superfoods and functional foods, and this article will detail the best ones to incorporate into the keto diet for health and longevity purposes.
What Are Keto Functional Foods?
Keto superfoods and keto functional foods are terms used interchangeably by many health and fitness bloggers. Again, the terminology has no discrete, technical definition among the scientific community. Nevertheless, keto functional foods are rich in micronutrients, fiber, essential fatty acids, and much more.
When it comes to keto superfoods and keto functional foods, the emphasis is largely on the micronutrient profile.
What are micronutrients, you ask?
Unlike macronutrients, such as protein and fat, your body only requires relatively small quantities of micronutrients for proper health and wellness. Micronutrients are generally split into several subcategories, including minerals, vitamins, and polyphenols.
Don’t misconstrue that to mean that micronutrients are “not important” for your health, as they are without question essential for surviving (and thriving).
In fact, many physicians and nutritionists feat that vitamin and mineral deficiencies will continue to be an alarming health concern on a global scale, as many people fall well short of the recommended daily intake (RDI) of micronutrients.
Moreover, plant polyphenols are natural micronutrients with a chemical structure containing many phenolic groups. There are over 8,000 known plant polyphenols that appear to play myriad roles in the human body, particularly as antioxidants.
Research suggests that these polyphenols can help treat things like type-2 diabetes, neurodegenerative disease, obesity, hypertension, cardiovascular disease, and much more.
Now, the more pertinent matter at hand is understanding how keto functional foods fortify your health by providing polyphenols and other micronutrients that are generally lacking in the diet.
In addition, these keto functional foods are low in net carbs (per serving), meaning they won’t take you out of ketosis.
Read on as we detail some of the best keto superfoods/functional foods and how to implement them into your diet for maximum benefit.
Top 7 Keto Superfoods and How They Can Benefit You
As the adage goes, “The difference between medicine and poison is in the dose.” What does that mean, exactly? It means that pretty much every substance out there has a beneficial dose and a harmful dose.
Even the most simple nutrient – water – can be lethal if you drink too much of it. Yet, in moderate amounts, water is the most crucial nutrient for survival. Many of the nutrients in superfoods abide by this principle. You don’t want to overeat superfoods, nor do you want to avoid them.
Ideally, you should eat keto superfoods daily in amounts that help you reach a clinically effective dose of the health-promoting nutrients they contain (don’t worry, we break it down into tangible numbers for you under each keto superfood).
Turmeric (Curcuma longa) is arguably the most popular plant superfood, thanks in part to its distinct golden color and seemingly ubiquitous benefits. It has been used for ages in alternative medicine for enhancing the immune system and treating a wide range of health conditions.
The compounds in curcumin that are responsible for many of its health benefits are known as curcuminoids, with a vast body of research demonstrating their therapeutic potential in humans.
Of particular importance is a curcuminoid called curcumin.
A contemporary meta-analysis contends that curcumin promotes proper cardiovascular function by regulating blood pressure, and also attenuates inflammatory (arthritic) pain in joint regions by bolstering the immune system.
Further evidence suggests that curcumin may antagonize sarcopenia (muscle-wasting) pathways at the genetic level.
In non-science lingo, this means curcumin appears to have anti-catabolic properties in the body, which is crucial for maintaining lean body mass.
The caveat with curcumin and other curcuminoids in turmeric is that they are not well absorbed through the gastrointestinal tract. Many naturopaths will actually administer turmeric injections for this reason.
If you choose to use an oral turmeric supplement, you’ll want to ensure it contains Longvida® Optimized Curcumin and/or a compound that enhances bioavailability of curcuminoids, such as piperine (black pepper fruit extract).
How Much Turmeric Should You Eat?
Pure turmeric powder makes for a tasty seasoning in many dishes, especially curry. On average, pure turmeric powder contains about 3% curcumin by weight; thus, one tablespoon (6.8 grams) of turmeric powder provides roughly 204 mg of curcumin.
Research suggests that 500 mg of curcumin per day is the minimal effective dose for therapeutic benefits (some studies go as high as 12,000 mg per day).
Hence, you’ll need 3+ tablespoons of pure turmeric powder daily to get much benefit from this keto functional food. Again, if you consume turmeric powder, you’ll want to supplement with something like piperine to enhance the bioavailability of curcumin.
The goji berry (also known as wolfberry) is native to high-altitude regions of Asia. Per gram, goji berries contain more vitamin C than oranges and more iron than spinach.
Goji berries are also a fantastic source of zeaxanthin – a carotenoid similar to lutein that promotes eye health.
Zeaxanthin also helps enhance the absorption of omega-3 essential fatty acids, such as EPA and DHA.
Goji Berries on Keto: How Much to Eat
Goji berries contain roughly half of their carb content in the form of dietary fiber and a high amount of protein. A one-ounce (28 gram) serving of Tibetan goji berries contains about 3.7 grams of net carbs, 3 grams of protein, 100 mg of zeaxanthin, along with 50% of the recommended daily intake (RDI) of vitamin A, 25% of the RDI of selenium, and 28% of the RDI of copper.
Cocoa beans are one of the Earth’s richest sources of polyphenols, especially flavonoids, tannins, and stilbenes. A bevy of studies has shown the potential for cocoa powder to enhance cardiovascular function, increase fatty acid oxidation, and support healthy blood glucose balance.[13, 14, 15]
Unsweetened Cocoa Powder on Keto
On keto, you’ll want to opt for unsweetened cocoa powder as opposed to things like dark chocolate (which is high in fat and often contains added sugar). An evidence-based dose of pure cocoa powder is around 2-3 tablespoons (30-45 grams) per day.
You might scoff at the idea that butter is a keto functional food, but we aren’t just talking about any butter – we are talking specifically about the grass-fed variety. In contrast to butter from grain-fed cattle, grass-fed butter contains over 400 essential fatty acids and micronutrients, including conjugated linoleic acid (CLA) and omega-3s which are beneficial for weight loss and cardiovascular health.
How Much Grass-fed Butter Should You Eat?
For practicality purposes, simply eat grass-fed butter as necessary to help meet your total daily fat intake on keto. This doesn’t mean you should be getting all of your dietary fats from just grass-fed butter, but rather in conjunction with other healthy fat sources.
Per tablespoon (14 g), grass-fed butter provides about 12 g of fat and a little over 100 calories.
Many keto advocates like to toss a tablespoon or two of grass-fed butter into their morning coffee for the energy boost and healthy fat content. You can also use it for pan-frying vegetables and meats.
In terms of phytonutrient composition, raspberries are the most impressive of any berry, packing a high amount of quercetin, catechins, ellagic acid, and much more. The polyphenols in raspberries are some of the more promising phytonutrients out there, with research suggesting they have anti-inflammatory actions in the body and support the absorption of essential vitamins and minerals.
Moreover, raspberries are nature’s exclusive source of raspberry ketone (not to be confused with ketone bodies), which gives them their ruby hue. In vitro research demonstrates that raspberry ketone can significantly enhance catecholamine-induced lipolysis (which is science lingo for fat breakdown via adrenaline, noradrenaline, and dopamine).
Unfortunately, there is no human clinical evidence (at this time) that supports the efficacy of raspberry ketone for weight loss.
Raspberries on Keto: How Much to Eat
Per gram, red raspberries have the highest antioxidant capacity of all berries when they are ripe, as well as a high amount of polyphenols.
Roughly 100 grams of ripe red raspberries contains about 5 grams of net carbs and will provide a hefty antioxidant and polyphenol punch for health and longevity benefits.
You didn’t think you’d actually make it through a keto functional food article without hearing about coconut, did you? The coconut is the preeminent food of choice for pretty much everyone on keto, mainly because it’s the richest natural source of medium-chain triglycerides (MCTs).
Why are MCTs great for keto, you ask? These are a special sub-group saturated fats that your body digests in a much different fashion than long-chain saturated fats (which are absorbed through the lymphatic system).
MCTs are rapidly absorbed through the portal system and sent to the liver for energy production, thereby supporting ketone synthesis as well. Plus, coconut has a fairly light flavor that meshes well with many foods and recipes.
How Much Coconut Should You Eat?
One tablespoon of pure coconut oil has about 13 grams of fat, with around 6 grams of MCTs (mainly lauric acid). We recommend simply consuming it as necessary to help you meet your fat needs on keto.
The neat thing about coconut oil is that can be used topically to hydrate the skin, moisturize hair, and even fight off acne.
Finding the right nuts and seeds can be tricky on the keto diet since things like peanuts and sunflower seeds contain a modest amount of carbs. Chia seeds, however, are low in carbs and high in fiber, giving them a very low net carb total.
The chia seed comes from the South American plant Salvia hispanica and has been a nutritional staple in many civilizations since the 13th century. Chia seeds have a unique binding quality due to their high soluble fiber content, causing them to form a gel when mixed with water.
In other words, chia seed is a great source of prebiotic fiber (not to mention it contains a good amount of omega-3 essential fatty acids as well).
How Much Chia Seed to Eat Per Day
An ounce (28 grams) of chia seed provides upwards of 10 grams of fiber, 5 grams of omega-3 fatty acids, and over 30% of the daily recommended intake (RDI) for manganese, magnesium, and phosphorus.
Even 14-15 grams of chia seed per day can help increase your fiber intake on keto and promote feelings of satiety. (Try adding chia to a smoothie or Greek yogurt, the taste is fairly neutral.)
What about Avocado?
The avocado is undoubtedly a keto functional food, and we need to give it an honorable mention for the sake of objectivity. In fact, we have an entire article devoted to avocado nutrition if you want to learn more about its benefits: Avocado 101: Nutrition Facts & Benefits
These keto functional foods should be the carbless dieter’s go-to options on a daily basis for micronutrients, essential fatty acids, and prebiotic fiber.
Remember, micronutrients, like vitamins and minerals, are just as essential to your health and longevity as macronutrients. Many diseases and health complications actually stem from micronutrient deficiencies.
Does this mean you should drastically overhaul your keto diet and only eat superfoods? Of course not. Rather, try incorporating 3-4 servings of these keto superfoods in your diet on a daily basis and you’ll be sure to notice (and feel) the benefits.
Be sure to watch your sugar and calorie intake if you’re consuming several servings of keto functional foods like raspberries and Goji berries every day. There are several other “superfoods” that didn’t make it into this article simply because they contain too many carbs for keto, like acai berries, kale, and Montmorency cherries.
However, using a supplemental version of higher-carb functional foods – like Montmorency cherry powder – is a practical option on keto since it helps reduce associated carb intake.
 Alloway, B. J. (Ed.). (2008). Micronutrient deficiencies in global crop production. Springer Science & Business Media.
 Black, R. (2003). Micronutrient deficiency: an underlying cause of morbidity and mortality.
 El Gharras, H. (2009). Polyphenols: food sources, properties, and applications–a review. International Journal of Food Science & Technology, 44(12), 2512-2518.
 Petti, S., & Scully, C. (2009). Polyphenols, oral health, and disease: A review. Journal of dentistry, 37(6), 413-423.
 Lobo, R., Prabhu, K. S., Shirwaikar, A., & Shirwaikar, A. (2009). Curcuma zedoaria Rosc.(white turmeric): a review of its chemical, pharmacological and ethnomedicinal properties. Journal of Pharmacy and Pharmacology, 61(1), 13-21.
 Amalraj, A., Pius, A., Gopi, S., & Gopi, S. (2017). Biological activities of curcuminoids, other biomolecules from turmeric and their derivatives–A review. Journal of traditional and complementary medicine, 7(2), 205-233.
 Daily, J. W., Yang, M., & Park, S. (2016). Efficacy of turmeric extracts and curcumin for alleviating the symptoms of joint arthritis: a systematic review and meta-analysis of randomized clinical trials. Journal of medicinal food, 19(8), 717-729.
 Labban, L. (2014). Medicinal and pharmacological properties of Turmeric (Curcuma longa): A review. Int J Pharm Biomed Sci, 5(1), 17-23.
 Tayyem, R. F., Heath, D. D., Al-Delaimy, W. K., & Rock, C. L. (2006). Curcumin content of turmeric and curry powders. Nutrition and cancer, 55(2), 126-131.
 Goel, A., Kunnumakkara, A. B., & Aggarwal, B. B. (2008). Curcumin as “Curecumin”: from kitchen to clinic. Biochemical pharmacology, 75(4), 787-809.
 Demmig-Adams, B., & Adams, W. W. (2002). Antioxidants in photosynthesis and human nutrition. Science, 298(5601), 2149-2153.
 Huang, L. L., Coleman, H. R., Kim, J., de Monasterio, F., Wong, W. T., Schleicher, R. L., … & Chew, E. Y. (2008). Oral supplementation of lutein/zeaxanthin and omega-3 long chain polyunsaturated fatty acids in persons aged 60 years or older, with or without AMD. Investigative ophthalmology & visual science, 49(9), 3864-3869.
 Almoosawi, S., Tsang, C., Ostertag, L. M., Fyfe, L., & Al-Dujaili, E. A. (2012). Differential effect of polyphenol-rich dark chocolate on biomarkers of glucose metabolism and cardiovascular risk factors in healthy, overweight and obese subjects: a randomized clinical trial. Food & function, 3(10), 1035-1043.
 Ostertag, L. M., Kroon, P. A., Wood, S., Horgan, G. W., Cienfuegos‐Jovellanos, E., Saha, S., … & De Roos, B. (2013). Flavan‐3‐ol‐enriched dark chocolate and white chocolate improve acute measures of platelet function in a gender‐specific way—a randomized‐controlled human intervention trial. Molecular nutrition & food research, 57(2), 191-202.
 Allgrove, J., Farrell, E., Gleeson, M., Williamson, G., & Cooper, K. (2011). Regular dark chocolate consumption’s reduction of oxidative stress and increase of free-fatty-acid mobilization in response to prolonged cycling. International journal of sport nutrition and exercise metabolism, 21(2), 113-123.
 Dugan, M., Aldai, N., Aalhus, J., Rolland, D., & Kramer, J. (2011). Trans-forming beef to provide healthier fatty acid profiles. Canadian Journal of Animal Science, 91(4), 545-556.
 Gülçin, İ., Topal, F., Çakmakçı, R., Bilsel, M., Gören, A. C., & Erdogan, U. (2011). Pomological features, nutritional quality, polyphenol content analysis, and antioxidant properties of domesticated and 3 wild ecotype forms of raspberries (Rubus idaeus L.). Journal of food science, 76(4), C585-C593.
 Morimoto, C., Satoh, Y., Hara, M., Inoue, S., Tsujita, T., & Okuda, H. (2005). Anti-obese action of raspberry ketone. Life sciences, 77(2), 194-204.
 Chen, L., Xin, X., Zhang, H., & Yuan, Q. (2013). Phytochemical properties and antioxidant capacities of commercial raspberry varieties. Journal of Functional Foods, 5(1), 508-515.
 DebMandal, M., & Mandal, S. (2011). Coconut (Cocos nucifera L.: Arecaceae): in health promotion and disease prevention. Asian Pacific Journal of Tropical Medicine, 4(3), 241-247.
 Topping, D. L. (1991). Soluble fiber polysaccharides: effects on plasma cholesterol and colonic fermentation. Nutrition Reviews, 49(7), 195-203.