What Are Phytonutrients?
Phytonutrients are natural, plant-derived compounds that support life and offer protection – innately in plants but for plant-eating humans as well. For example, a 2014 meta-analysis found that the more vegetables eaten, the lower the risk of all-cause mortality1.
For plants, phytonutrients are important for healthy growth:
- Protection from UV radiation
- Help deterring pests
- Providing vibrant colors to attract pollinators
- Playing roles in tissue healing following injury
In the human body, phytonutrients can also influence health profiles and have been shown to:
- Act as direct antioxidants to reduce oxidative stress
- Stimulate production of internal antioxidant systems
- Support metabolic systems and regulate inflammatory responses
- Regulate cell proliferation and processes
- Regulate specific gene transcription and influence expression of genetic potential (epigenetics)
“Phyte” For Health
Why care about phytonutrients? The human body needs phytonutrients in a different way than it needs nutrients like protein, vitamins, and minerals. Phytonutrients are uniquely able to satisfy free radicals circulating in the body looking for electrons. By providing electrons, phytonutrients prevent free radicals from taking electrons from proteins or other nutrients, a “theft” that leads to oxidative stress.
Free radicals are unstable molecules formed during both natural body processes and from exposure to toxins. Some studies have found that many phytonutrients increase activity of Nrf2 (nuclear factor (erythroid-derived 2)-like 2), ultimately increasing antioxidant and detoxification activity2.
The colors of food have long been associated with improving health conditions. Green foods help improve diabetes, immunity, protects against cancer, and enhances gene expression. Red foods align with the cardiovascular system by protecting the heart and blood vessels. Red is also responsible for building muscle mass and skin protection. White foods, even though not as colorful, still yield a tremendous amount of immune system support, decreases allergies, reduces inflammation, helps maintain weight and lowers cholesterol. Purple improves memory, protects again cancer, improves the gut and keeps a healthy heart. Yellow or orange foods additionally protect the gut, protects our eyes and skin, fights cancer, and improves immunity.
Whole Food Bioactivity
The idea of “whole food bioactivity” describes the concept that bioactive phytonutrients consumed from whole foods produce stronger health benefits than when the phytonutrient is isolated and consumed alone3,4. This idea also includes the notion that some phytonutrients in foods have a synergistic effect when eaten together.
Eat the Rainbow
Many phytonutrients are colored pigments, such as
- Orange-colored beta-carotene
- Red-colored lycopene
- Blue/purple-colored anthocyanidins
These phytonutrients are not “essential” for life, but they may contribute to optimal health. Increased intakes have been associated with protection against various chronic health conditions5. Because different plant colors are associated with the beneficial protection of phytonutrients, encouraging diversity of plant-based colors in a given meal can be a great method for improving diet choices.
Gallic Acid Equivalence
Scientists can quantify “total phenolics” between different plants by measuring Gallic Acid Equivalence (GAE), which can be used to compare the amounts of phytonutrients and the total phenolic compound content of different foods. Phenolics are a group of phytonutrients that include phenolic acids, stilbenes, flavonoids, and condensed tannins.
Phenolics are universally present in plant-derived foods and have been long-linked to the health properties of a plant-based diet. One grouping of phenolics, called polyphenols, include non-energy, non-nutritive, secondary metabolites found in plants6,7. Polyphenols are associated with several beneficial properties:
- Antioxidant activity
- Anti-inflammatory activity
- Platelet aggregation reduction
Polyphenols have also been linked to lower risk of major chronic conditions by improving6:
- Lipid profiles
- Endothelial function
- Glucose metabolism
- Beta-cell function
Polyphenols may help support healthy:
- Blood pressure
- Levels of oxidation markers
- Resolution of the inflammatory response
- Blood vessel function
The Phytonutrient Gap
Data analysis from the National Health and Nutrition Examination Surveys (NHANES) found that the percentages of Americans that met fruit and vegetables intake recommendations from the 2005 Dietary Guidelines for Americans was only between three and 12 percent8,9.
For specific phytonutrient intake, the analysis showed that Americans failed to meet recommended levels in every color category; on average, eight of every 10 Americans have some sort of gap in phytonutrient intake8,9. The biggest gap is the blue/purple fruit and vegetable group, with only 12% of people meeting the median intake of those phytonutrients. While the number of Americans consuming green fruits and vegetables is slightly hirer, the percentage is still under 30% of the recommended intake8,9.
Consumption of fruits and vegetables in American is subpar, yet we know that 10 servings of fruits and vegetables per day can add years to your life. While 10 servings may seem daunting, if you break it into meals and snacks throughout the day, it is actually quite manageable.
For example, along with your other protein, fat, and carbohydrate sources, 10 servings of fruits and vegetables could look like this during the day:
- 1 cup cooked red bell peppers and spinach in your omelet (2 servings: 1 red, 1 green)
- 1 cup of raw blueberries (1 serving: 1 blue)
- 1 apple (1 serving: 1 white)
- 3 loose cup salad (1 serving: green)
- 1 cup raw carrot/cucumber/radish vegetable mix (1 serving: orange/green/white)
- 1 cup cherry tomatoes (1 serving: red)
- ½ cup cooked cauliflower + ½ cup cooked broccoli (2 servings: 1 white, 1 green)
- 1 small cooked sweet potato (1 serving: orange)
Nutrient Deficiencies and Dietary Recommendations
It is no coincidence that both nutrient deficiencies and chronic conditions are at an all-time high. A high-quality diet paves the way for high-quality health, and a diet lacking the proper nutrients – replaced with processed food typical of the standard American diet (SAD) – is one that is prone to chronic health problems.
Five Shortfall Nutrients of Public Health Concern in Americans10,11
- Vitamin D
- Iron (for premenopausal women and adolescents)
According to the 2015-2020 Dietary Guidelines for Americans, daily vegetable intake should be 2.5 cups and daily fruit intake should be two cups (2,000 calorie diet)1. More than 90 percent of Americans do not meet this minimum12,13. The Guidelines also stress the importance of eating a variety of vegetables, but Americans fall short12,13:
- More than 80 percent do not eat enough green vegetables.
- More than 90 percent do not eat enough red and orange vegetables.
- Potatoes account for more than 25 percent of all vegetable consumption.
- Approximately 100 percent do not eat enough whole grains.
The lack of proper nutrients and excessive consumption of processed food is ultimately linked to chronic health conditions, and those related to obesity (ischemic heart disease, stroke, cancer, diabetes, Alzheimer’s disease and other dementias) are among the leading causes of death in the United States14,15,16.
Limit Added Sugar in Your Diet
Added sugars in processed food and beverages are a large contributor to weight gain and are linked to health problems like obesity, type 2 diabetes, digestive disorders, and heart disease. Added sugars are the sugars and syrups added to foods or beverages when they are processed or prepared – not naturally occurring sugars found in fruit and milk. Typically speaking, lactose, found in milk, and fructose, found in fruit, are naturally occurring. The problem arises when yogurt products that contain lactose, for example, are flavored with an added sugar such as corn syrup or honey. New label guidelines require not only the grams for sugar, but also specifically for added sugars. This helps consumers decipher the ingredient list for full disclosure of products.
You might see the following added sugars on ingredient labels:
|· Brown sugar||· Corn sweetener|
|· Corn syrup||· Dextrose|
|· Fructose||· Glucose|
|· High-fructose corn syrup||· Honey|
|· Lactose||· Malt syrup|
|· Maltose||· Molasses|
|· Raw sugar||· Sucrose|
And you might see the following products include these added sugars:
- Sugar-sweetened beverages (soda, juice)
- Grain-based desserts (cakes, cookies)
- Dairy desserts (ice cream)
The 2015-2020 Dietary Guidelines for Americans recommends eating less than ten percent of totally daily calories from added sugars, yet Americans six years old and older consumed approximately 14% of total daily calories from added sugars between 2003 and 2010. Consumption varies by age, sex, race, and ethnicity as well as by socioeconomic status and behavioral characteristics. Health officials recommend replacing sugar-sweetened food and beverages with plain water and fruit.
Carbohydrates, Healthy Fats, and the Under-appreciated Role of Plant Proteins
Carbohydrates are an essential macronutrient – necessary for most body functions. Carbohydrates are found in just about all foods, and rightfully so, as a main energy source. Fruits and vegetables are primarily categorized as carbohydrates; whole grains are categorized this way as well. Recognizing quality carbohydrates is key. Simple and complex carbohydrates turn into glucose for energy. Simple carbohydrates digest quickly, whereas complex carbohydrates have more fiber, requiring longer digestion. There are refined carbohydrates within the simple carbohydrate category including white breads, cakes, and soda. Complex carbohydrates make up most of your vegetables, nuts, seeds, and whole grains.
While fat is a macronutrient that provides energy, it is best to consume unsaturated fat options in place of saturated and trans fat. Healthy fats include monounsaturated fatty acids, polyunsaturated fatty acids, and omega fatty acids. Plant-based oils commonly make up the mono- and polyunsaturated fat category, referring to olive or grapeseed oil for example. These fats decrease heart disease risk and improving cholesterol levels.
Amino acids are the building blocks of protein, another macronutrient needed for quality health. However, when we hear the word protein, sources such as poultry, red meat, or fish often are first choices. Plant protein, or alternative proteins, yield powerful benefits that are under-appreciated in today’s meat-minded society. These include things like tempeh, tofu, lentils, and chickpeas to name a few. A long-standing myth is that alternative proteins needs to be paired with a grain, such as rice, in order to obtain the essential amino acids. Many plant foods contain essential amino acids as is, including quinoa and buckwheat. Plant-based options provide more fiber with little or no saturated fat and less calories than a meat comparison making Meatless Mondays a positive trend that most can benefit.
Food Quality Score: Aiding in Nutrition Discussions
Food Quality Score (FQS) is an assessment of eating habits by food. FQS is linked to the consumption of fruits and vegetables, and it is associated with an individual’s risk for chronic health conditions and specific outcomes for coronary artery disease17.
An individual’s relative risk declines with higher scores based on the assessment tool. For example, higher consumption of fruits and vegetables lowers the risk of all-cause mortality1. The increased consumption of monounsaturated and polyunsaturated fats, paired with a decreased consumption of saturated fats and trans fat, also affects mortality17.
Nutrient Deficiency and Chronic Disease
According to the 2015-2020 Dietary Guidelines for Americans, daily vegetable intake should be 2.5 cups and daily fruit intake should be two cups (based on a 2,000 calorie diet)18. More than 90 percent of Americans do not meet this minimum19,20. The lack of proper nutrients and excessive consumption of processed food is ultimately linked to chronic health conditions, and those related to obesity (ischemic heart disease, stroke, cancer, diabetes, Alzheimer’s disease and other dementias) are among the leading causes of death in the United States21,22,23.
Food Quality Score (FQS)
FQS provides practitioners a simple tool to aid in nutrition discussion, ranking healthy and unhealthy food items into categories and quintiles. Based on an individual’s consumption habits, a score is associated and tallied at the end of the questionnaire. Individuals answer a series of questions such as “How often do you usually eat fruits?” and “How often do you usually eat green-leafy vegetables?” with answer choices ranging from “never or less than once a month” to “every day or almost every day.”
The FQS shows the association between specific dietary habits and cardiometabolic health issues including17:
- Glucose control in type 2 diabetes and pre-diabetes
Evidence from prospective studies and meta-analyses have demonstrated that higher intake of plant-based foods is associated with lower risk of hypertension, diabetes, CVD, cancer and mortality. This includes fruit, different types of vegetables, whole grains, nuts, and other plant-based foods24,25,26,27.
FQS offers practitioners an opportunity to conduct targeted interventions with their patients to improve diet and lifestyle habits, reduce the risk of chronic disease, and improve quality of life.