What are phytochemicals and why do we need them?
Phytochemicals (also called phytonutrients) are naturally occurring compounds found in plants, such as fruits, vegetables, herbs, and spices. Although they may not be considered essential nutrients, phytochemicals work synergistically with vitamins and minerals to support antioxidant status, healthy immune and inflammatory responses, and digestive and metabolic health.
Polyphenols are a diverse group of phytochemicals that includes flavonoids (found in berries, tea, and citrus fruit), stilbenes (found in grapes, red wine, and berries), lignans (found in seeds, whole grains, legumes, and cruciferous vegetables), and phenolic acids (found in coffee, whole grains, fruits, and spices). Other common types of phytochemicals include carotenoids (found in carrots, sweet potatoes, spirulina, and leafy greens) and glucosinolates (found in cruciferous vegetables). These phytochemicals have been shown to support multiple important physiological processes in our bodies, including normal inflammatory and immune responses, antioxidant status, metabolic health, and heart health.
There is a wide diversity of phytochemicals supporting various aspects of our health. Moreover, consuming a variety of phytonutrient-rich superfoods together has been shown to impart synergistic effects enhancing their efficacy.
The role of phytochemicals in supporting antioxidant status
Including plenty of plant-based superfoods rich in phytochemicals in our diet may help protect our cells from damage caused by normal metabolic processes, such as oxidative stress. A systematic review and meta-analysis of sixteen studies with 833,234 participants found that higher phytonutrient consumption significantly increased serum concentrations of compounds supporting antioxidant status (including beta-carotene, vitamins C and E, and folate) and reduced homocysteine, lipid oxidation, DNA oxidation, and protein oxidation biomarkers.
Several phytonutrients have been shown to play an important role in promoting antioxidant status. Carotenoids, flavonoids, chlorophylls, polyphenols, and anthocyanins may be instrumental in scavenging reactive oxygen species and supporting healthy inflammatory responses, liver function, and detoxification pathways. Lignans, carotenoids, and polyphenols may also modulate adaptive cellular response pathways that influence the expression of genes encoding for antioxidant enzymes, including the Nrf2 pathway, which plays an important role in protecting cells from oxidative stress.
Due to their high polyphenol and stilbene content, grape seed and skin extracts also play an important role in supporting antioxidant status. A meta-analysis of nineteen studies found that those supplemented with GSSE exhibited a significant decrease in biomarkers of oxidative stress. Another meta-analysis of seventeen randomized controlled trials, with a total of 633 participants, examined the effect of grape products containing polyphenols on oxidative stress. The review found evidence that those supplemented with GPCP showed significant increases in total antioxidant capacity, oxygen radical absorbance capacity, and superoxidase dismutase (an enzyme that mitigates cellular oxidative stress).
The role of phytochemicals in metabolic health
Numerous studies have found that consuming plant foods rich in phytochemicals (such as berries, spirulina, chlorella, stinging nettle, grape seed extracts, and barley grass) may support metabolic health, energy production, healthy blood sugar and lipid metabolism, and healthy body composition. Additionally, the phytochemicals flavonoids, polyphenols, and anthocyanins have all been shown to support lipid metabolism, normal insulin responses, and healthy weight.
For example, a systematic review and meta-analysis of ten randomized controlled trials, with a total of 539 participants, evaluated the effect of Chlorella vulgaris supplementation on the lipid profile in adults. The authors found that those supplemented with chlorella showed significantly lower total cholesterol and LDL cholesterol. A randomized controlled trial (N = 38) examined the effects of increased consumption of phytonutrient-rich fruits and vegetables on biomarkers associated with the presence of gestational diabetes mellitus. In the intervention group, women with GDM were instructed to consume one cup of whole berries and one cup of leafy vegetables daily. When compared to the control, the intervention group showed increased fiber and phytonutrient intake, higher HDL cholesterol, lower blood glucose, and lower interleukin-6 biomarkers.
A review study exploring the role of barley grass in metabolic health found that this phytonutrient-rich superfood may support blood sugar metabolism. More specifically, the flavonoid saponarin, found in barley grass and its extracts, was shown to modulate postprandial blood glucose (i.e. blood sugar levels after eating a meal), which can promote healthy blood sugar metabolism. Another review study explored the effects of spirulina on weight loss and blood lipids. The authors found that those supplemented with spirulina reported reduced body fat, waist circumference, BMI, appetite, LDL cholesterol, triglycerides, and total cholesterol, while also reporting increased HDL cholesterol.
In addition to the maintenance of healthy blood sugar, lipids, and normal weight, optimal energy production and metabolism are also essential components of overall metabolic health. Besides being rich in phytochemicals, superfoods like spirulina, chlorella, barley grass, stinging nettle, and wheatgrass also provide vitamins, minerals, amino acids, and essential fatty acids that help support energy production at the cellular level and may lead to more sustained energy and vitality throughout the day without relying on stimulants like caffeine.
The powerful phytochemicals found in plant-based superfoods offer a compelling approach for supporting antioxidant status and metabolic health. As scientific research continues to uncover the intricate mechanisms of action behind the multitude of different phytochemicals, it remains clear that integrating a variety of colorful fruits, vegetables, herbs, and spices into our diet isn’t just a trend, but a science-based strategy for supporting our overall health and well-being from the inside out.
Learn more about phytochemicals, antioxidant status, and metabolic health:
Functional Flavonoids in Blueberries Support Redox Balance
Review Explores Impact of Phytochemicals and Probiotics on Oxidative Stress
Effects of Citrus Flavonoids on Lipid Metabolism in NAFLD Patients
American Ginseng May Support Healthy Glucose Metabolism
Why Flavonoids Have an Important Place in Children’s Diet
By Antonia Toupet, PhD
Designs for Health has been dedicated to being the most trusted source for superior quality, science-based nutritional products for nearly three decades. We’re committed to maximizing successful health outcomes by providing healthcare practitioners with comprehensive support through our extensive product line, ongoing clinical education, and practice development programs. The blogs we publish here cover a range of topics, including new and original approaches to diet and healthcare, analyses of the latest cutting-edge research, deep-dives into specific nutrients, botanicals, nutraceuticals and more, all fully referenced for those who want to dig deeper into the primary literature.
