With the sun hiding behind wintry clouds, the coldest season of the year is an ideal time to add some sunshine and warmth to your diet by eating more citrus fruits! Bright, colorful, fragrant, refreshing, and juicy, citrus fruits are not only delicious for their balanced tart and sweet taste, they are also an essential part of everyday nutrition, packing powerful health benefits beneath that tough, leathery rind. Citrus fruits are rich in multiple nutrients such as vitamin C, flavonoids, and fiber which confer vascular protection, reduce inflammation, improve gastrointestinal function and health, and play an important role in preventing conditions like diabetes, cancer, neurological disease.
Their benefits have been celebrated since ancient times. Thought to have originated from Southeast Asia, citrus fruits were wildly popular wherever they spread. The citron (Citrus medica) was and in many cases remains a prominent fixture in religious ceremonies and festivals such as the Jewish Feast of Tabernacles (Sukkot), which finds its roots as a festival thanksgiving for the fruit harvest. The Greeks knew citrus fruits as “Thyon," while the Romans called them “Citrus."
From the citron, other hybrid citrus species began springing up such as oranges, lemons, limes, pomelos, mandarins and others. Spanish travelers introduced the sweet orange to the American continent, while it is believed that Christopher Columbus brought citrus seeds to be planted on the island of Haiti on his second voyage in the year of 1493. Wherever they were found, precious citrus fruits were used as a fragrance and as a flavor added to sweets and tea. Citrus fruits were well known for their medicinal properties and were used to combat sickness, intestinal ailments, skin conditions, gout, scurvy and even used as an antidote to poison and as an antiseptic during times of plague.
Multifarious applications aside, the ancients were clearly onto something.
Today, we know much more about what gives citrus its superior standing. I would like to highlight some nutrients and phytochemicals that give those fruits their remedy qualities:
Vitamin C (ascorbic acid) is one of the most popular vitamins in the world. Citrus fruits are notably rich in vitamin C. This vitamin is needed to form and maintain healthy skin, bones, blood vessels and connective tissues. Vitamin C plays an important role in supporting the immune system and also acts as an antioxidant that might help protect your cells against the effects of free radicals and fight inflammation.
By reducing inflammation, vitamin C may prevent or delay heart disease conditions like arthritis and some types of cancer. Vitamin C helps the body to absorb iron from plant foods (the non-heme iron).
Therefore, eating a citrus fruit alongside plant foods like leafy green vegetables, nuts, seeds and legumes will help the body better absorb iron. Citrus fruits are rich in vitamin C that is essential for building healthy body tissues. But the protective benefits of citrus fruits are not limited to only one nutrient, they expand to numerous nutrients, among them a large plant compound family called the Flavonoids.
Flavonoids are plant-based nutrients (phytonutrients) responsible for the plant qualities such as its bright color and the familiar aroma. Citrus fruits represent an important source of dietary flavonoids including hesperidin, hesperetin, naringin, naringenin, diosmin, quercetin, rutin, nobiletin, tangeretin and others. Flavonoids also have multiple therapeutic benefits.
Studies indicate that citrus flavonoids protect the cells against the damage of free radicals. Through a direct scavenging of free radicals, citrus flavonoids can reduce inflammation. Consequently, those anti-inflammatory pathways provide therapeutic benefits against cancer, neurodegenerative disorders, atherosclerosis, cardiovascular disease (CVD) and against diabetes. For instance, Flavonoids may have preventive action against atherosclerosis and CVD by scavenging free radicals, Flavonoids inhibit low-density lipoprotein - “bad” cholesterol (LDL) oxidation, reduce oxidative stress and inflammation, improve endothelial function and arterial blood pressure.
Citrus flavonoids can protect against diabetes by improving glucose tolerance, increasing insulin secretion and sensitivity, and decreasing insulin resistance and also may play a significant role in the development of antiobesity agents, reducing obesity and adipose tissue inflammation.
Last but not least, citrus flavonoids have the ability to modulate gut bacteria (microbiome) composition and activity and exert beneficial effects on intestinal barrier function and gastrointestinal (GI) inflammation. This effect on GI microbiome suggests that intake of citrus flavonoids can contribute to improved GI functioning and health. With all the health promoting qualities mentioned above, we cannot ignore the beneficial effects of a well-known macronutrient, the Dietary Fiber.
Dietary Fiber is a type of complex carbohydrate found in plant foods. It is made of many sugar molecules linked together in a way that cannot be entirely digested in the small intestine. Dietary fiber can be divided into two types: soluble and insoluble fiber, and citrus fruits contain some of each kind.
Soluble fiber can help lower LDL cholesterol, consequently reducing cardiovascular disease. This type of fiber can also help improve glucose control by slowing the absorption of sugar resulting in better blood sugar levels. Insoluble fiber can help relieve constipation by helping food move more efficiently through digestive system and increases stool bulk.
Citrus fruits are also abundant in multiple other nutrients, including potassium, folate, calcium, thiamin, niacin, vitamin B6, phosphorus, magnesium, copper, riboflavin and pantothenic acid, making consumption of citrus fruits as part of a balanced diet is essential to our health.
However, it is important to note that certain citrus fruits can interact with medications. Grapefruit, pomelo and orange fruits and fruit juices can be a problem when taking some prescription medications. Those fruits can affect how the medication works by affecting absorption, distribution and metabolism of certain medications.
If you are taking medications, please consult your healthcare provider before adding those fruits to your diet. Otherwise, grab a slice of citrus and let their powers set to work! Citrus fruits go well in almost any meal. Enjoy the sweet and tangy freshness of citrus fruits in:
- Salad dressings (download handout)
- As a snack
- Add it to your yogurt or oatmeal
- Add a few slices to your fresh water (download handout)
Anna Nekrich is a registered dietitian at the University of Washington Medical Center. Outside of work she enjoys ballet classes, outdoor activities, reading, baking and spending time with her friends, her husband, their two daughters and cat.
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