January 2021 Issue

CPE Monthly: Health Benefits of Seeds
By Ginger Hultin, MS, RDN, CSO
Today’s Dietitian
Vol. 23, No. 1, P. 46

Suggested CDR Performance Indicators: 8.1.3, 8.1.4, 8.3.1
CPE Level 2

Take this course and earn 2 CEUs on our Continuing Education Learning Library

As consumer interest in nutrient-rich, functional foods continues, seeds are recognized as a category that offers unique health benefits. Because of their nutrient density, potential health benefits, and versatility in culinary use and flavor, seeds are an important part of the human diet. A large food category, “seeds” encompasses grains, legumes, and nuts. The foods that many people typically refer to as seeds fall into a smaller category that comes from fruits, vegetables, and flowers.

This continuing education course examines the role seeds play in the modern diet. It provides information on the history of seeds in the human diet and explores the three large categories of seeds: whole grains and cereals, legumes, and nuts. It reviews nutritional content of seed categories and explores potential health benefits of including these foods in the diet.

This course focuses on the more commonly understood categories of seeds, including hemp, sunflower, and pumpkin seeds and the pseudocereals chia, sesame, and flaxseeds.

Seeds in Human History
Seeds, which are the structure that enables plants to create new generations, are rich in nutrients to protect the embryonic plant held inside. Seeds fall into three main categories: grains and cereals, legumes, and nuts. They also include smaller categories, such as other edible fruit, flower, and vegetable seeds, including hemp, sesame, sunflower, and pumpkin/squash seeds.1

Within these categories, seeds have unique health properties. Evidence suggests that ancient human cultures in the Middle East, Asia, and Central and South America began intentionally harvesting seeds from plants to harvest in clearings before the agricultural revolution because of their nutritional and energy benefit to the human diet. The first seeds grown intentionally likely were einkorn, emmer wheat, barley, lentils, peas, bitter vetch, and chickpeas.1

Seeds contain energy and vital nutrients for human health, including protein and B vitamins. There are examples of cultures reliant on a particular seed that have suffered from deficiency during times of increased industrial processing, resulting in a product stripped of certain nutrients. For example, in the 19th century, parts of Asia experienced a beriberi plague when milling machines started stripping the bran layer of rice, removing the B vitamin thiamine. Parts of Europe and the United States experienced pellagra, a niacin deficiency, in the 18th and 19th centuries when corn was processed with alkaline water.1

Rice, corn, and wheat are seeds and staples of nutrition for cultures around the world. From ancient history to modern day, seeds play a vital role in human health and nutrition.

The 2015–2020 Dietary Guidelines for Americans (DGA) recommend that at least one-half of grain servings consumed per day should be whole grains to decrease the risk of chronic conditions. They also suggest eating a variety of protein foods that include seeds such as legumes (beans and peas), nuts, and soy products.2

Studies show that many Americans aren’t meeting these recommended guidelines. For example, whole grain intakes fall short of the DGA, with studies suggesting less than 10% of US adults consume the daily recommended three or more servings of whole grains.3 A National Health and Nutrition Examination Survey study from 2007–2010 found that 88.5% and 52.2% of the US population doesn’t meet the daily requirement for vitamin E and magnesium, respectively; many seeds are a good source of both.4

Categories of Seeds
When consumers mention seeds in the diet, they may think of sunflower, hemp, chia, flax, sesame, or pumpkin seeds, which commonly are consumed as a garnish or snack. These actually fall into a subcategory of seeds classified as flower, vegetable, and fruit seeds. Hemp and cacao seeds are also potential sources of nutrition but don’t clearly fit into any of these or the three broader categories discussed in this course.

While sunflower, hemp, chia, flax, sesame, and pumpkin seeds will be the focus of this course, a more extensive analysis will first be offered. As mentioned, seeds fall into three broad categories: grains and cereals, legumes, and nuts. It’s important to understand what types of seeds are consumed in the human diet before assessing their role in clients’ health and wellness.

Grains and Cereals
Cereal grasses include an edible grain. Cereals in this category include wheat (emmer/farro, Kamut, spelt, durum), barley, fonio, oats, rye, rice, maize, millet, sorghum, teff, and triticale. These seeds have played a critical role in the human culinary culture for thousands of years because both bread and beer are made from this family.1

Pseudocereals are plants that produce seeds consumed as grains, though botanically they’re neither grasses nor cereal grains. This category includes amaranth, chia seeds, flaxseeds, quinoa, and sesame seeds.5,6 Pseudocereals are members of the grass family though are commonly consumed in ways similar to other cereals.1,3

Grains and cereals including pseudocereals are a diverse group of seeds with a variety of nutrients and health-promoting compounds. Highlights of this group include flax and chia due to their omega-3 alpha-linolenic acid (ALA), fiber, and high protein content.

Note that whole grains are limited in the amount of the amino acids lysine and threonine they contain, but studies show the body can combine amino acids naturally through consuming a variety of foods in the diet.7 It’s unnecessary to educate clients that they must combine grains with other foods for this reason. The more beneficial education for clients is to focus on a variety of foods and diversity in the diet so they gain access to many types of vitamins, minerals, and antioxidants that could benefit health.

In a review of case-control research, the World Cancer Research Fund and American Institute for Cancer Research state that whole grains in the diet likely play a role in cancer risk reduction. Some reasons why this link is so strong, particularly with colorectal cancer risk reduction, are that whole grain consumption may help lower body adiposity and BMI, decrease risk of type 2 diabetes, and have a positive influence on some hormones in the body such as estrogen. They’re also a good source of many vitamins, minerals, and antioxidants, including magnesium, which has been inversely associated with colorectal cancer.3

Many whole grains go through a process of refining, which removes the outer bran and inner germ, leaving only the endosperm to create a softer flour or baked product. This process greatly reduces the nutrients, including fiber, B vitamins, iron, magnesium, and vitamin E.3

Popular seeds currently consumed in the diet, chia and flaxseeds, will be discussed in greater detail later in this course.

Members of the bean and pea family, legumes bear pods that contain seeds such as fava/broad beans, chickpeas/garbanzo beans, lima/tepary beans, common beans (white, red, kidney), lentils, peas/black-eyed peas, mung beans, adzuki beans, peanuts, and soybeans.

Legumes are high in protein—as much as two to three times higher than wheat or rice. A large category of seeds, legumes comprise 20 different species with varieties native to Europe, India, East Asia, Africa, and Central and South America.1

Legumes are an important source of protein, iron, B vitamins, folic acid, fiber, and unsaturated fatty acids in the diet.1,8 Soybeans in particular contain unique health-promoting antioxidants called isoflavones, which are tied to cardiovascular and bone health as well as anticancer benefits.1,9 Soybeans also boast the highest amino acid score of any legume—most legumes are limited in methionine.9

Again, there’s no need to combine these seeds with others that have higher levels of this limiting amino acid. The body stores all amino acids to use as needed, so individuals don’t need to be concerned about foods that contain limiting amino acids (defined as lower levels of an essential amino acid).7

Nuts, which are nutrient- and calorie-dense large seeds enclosed in hard shells, include almonds, Brazil nuts, cashews, chestnuts, coconut, hazelnuts, macadamia nuts, pecans, pine nuts, pistachios, walnuts. They’re unique in that they’re generally larger than grains and legumes, richer in oil, and many (though not all) can be eaten without further cooking or processing.1

Nuts are versatile and are eaten raw or roasted and made into paste, butter, nondairy beverages, and oils. All nuts have unique properties, culinary uses, and potential health benefits. Almonds are the world’s largest nut crop. Brazil nuts contain a particularly high amount of selenium. Cashews contain more starch than many other nuts (comprising 12% of their weight). Macadamia nuts have the highest fat content of all tree nuts. Coconuts are the largest of all nuts and are widely used throughout the world in a variety of cuisines.1

All nuts are dense in energy because of their fat content; some are composed of 50% fat or more. Nuts contain unsaturated fatty acids, though the fatty acid composition among nuts varies. Almonds, hazelnuts, pistachios, and cashews are higher in monounsaturated fatty acids, while walnuts are higher in polyunsaturated fatty acids. Walnuts are especially rich in ALA.10

Nuts also contain fiber, vitamins, and minerals—especially vitamin E and folic acid—and generally comprise 15% to 20% protein. However, they’re limited in the amino acid lysine.1

Health Benefits of Commonly Consumed Seeds
All seeds are nutrient dense, supportive of human health, and versatile for culinary preparations in their own way. They boast high fiber and protein content, unsaturated fatty acids such as essential fatty acids, vitamins and minerals, and antioxidants and bioactive compounds, all attributes that have made them a staple in the human diet since ancient times. Most seeds are sources of vitamin E and folate, but nutrients vary by type. Though they all have a variety of limiting amino acid content, there’s no need to combine these seeds to create “whole” or “complete” proteins.

Epidemiologic studies have found an association between consuming seeds and a reduced risk of some cancers, heart disease, and diabetes.1,11 This is likely because of the nutrients and antioxidants they contain in addition to their fiber and healthful fat content.

The following explores the unique benefits of commonly consumed seeds.

Chia Seeds
Technically grains rather than fruit, flower, or vegetable seeds, tiny chia seeds are native to Guatemala and Mexico but now are grown throughout parts of Central and South America, Australia, and the southwestern United States.12 A staple of pre-Columbian civilizations in America, chia seeds have been an important part of a nutritious diet since the era of the Mayan and Aztec civilizations.5,12 Aztec soldiers carried chia seeds into battles and on expeditions in the 16th century for trade, religious ceremonies, and making goods such as cosmetics.13

Chia seeds contain the omega-3 fatty acid ALA, which can convert in the body to the essential fatty acids EPA and DHA.1 Chia seeds are one of the richest botanical sources of ALA and can be used as animal feed to increase the omega-3 content of eggs, poultry, pork, and other meats.5 They also contain calcium, phosphorus, potassium, magnesium, iron, zinc, and the B vitamins riboflavin, niacin, and thiamine, as well as antioxidant phenolic compounds such as rosmarinic acid, protocatechuic acid, caffeic acid, and gallic acid.12,13

Chia seeds are a source of dietary fiber, containing more than other seeds such as amaranth, quinoa, and corn. The fiber in chia seeds is primarily lignin, cellulose, and hemicellulose; in addition, they contain mucilaginous soluble fiber.13

The nutrient and fiber content of chia seeds may contribute to some of their potential health benefits. There are human studies on the consumption of chia seeds that show their promise for reducing total cholesterol and LDL cholesterol while increasing HDL cholesterol.13

A small study of 26 participants with overweight or obesity experienced statistically significant reductions in body weight (-1.1 kg, p<0.05) and waist circumference (-1.9 cm, p<0.05), reduced total cholesterol (p=0.04) and very low–density lipoprotein cholesterol (p=0.03), and increased HDL cholesterol (p=0.01) after 12 weeks of 35 g/day of chia seed flour.13,14 The average daily intake of calories, macronutrients, and dietary fiber wasn’t significantly different between the intervention and control groups, though researchers did observe higher protein intake in the intervention group than in the control group in the fourth week of the trial.14

Human studies on chia seeds for reducing blood pressure are mixed at this time, though research on their blood sugar–lowering effects are more promising. Human studies, while having varying results, generally show that chia seed consumption leads to lower blood glucose and reduction in peak glucose.13

Chia seeds have versatile culinary uses; they’re commonly made into chia “pudding” by adding dairy or plant-based milk, fruit, and nuts, and they can be sprinkled into yogurt or added to granola, salads, and salad dressings.

There’s evidence that humans have been consuming flaxseeds since ancient times. Canada is currently the largest producer of flax, but the seed is cultivated around the world.15 As with chia seeds, flaxseeds contain ALA in addition to lignans and soluble fiber, phenolic compounds, and vitamins and minerals.1,15 They’re a good source of potassium, calcium, magnesium, phosphorus, iron, vitamin A, and phenolic compounds ferulic acid, chlorogenic acid, and gallic acid.15

Similar to chia seeds, the functional health benefits from flaxseeds likely have to do with their high fiber content and inclusion of a variety of nutrients and antioxidants. Uniquely, the presence of omega-3 fatty acids in flax may be responsible for reducing inflammatory mediators such as prostaglandin E2, leukotriene B4, tumor necrosis factor alpha, interleukin, and cytokines.15

Large epidemiologic studies show diets rich in phytoestrogens, found in the lignans in flaxseeds, may reduce the risk of hormone-dependent cancers, CVD, and bone density problems. Flax, like chia seeds, is mucilaginous, increasing intestinal bulk, which can help treat constipation, irritable bowel syndrome, and diverticular disease.15

In a study of 110 participants with hypertension, 30 g of milled flaxseeds per day over a six-month period increased plasma levels of ALA by 2.8-fold; systolic blood pressure (SBP) decreased a non–statistically significant 10 mm Hg, while diastolic blood pressure (DBP) decreased a non–statistically significant 7 mm Hg. The results became significant in participants who started with an SBP of >140. This group saw a reduction of 15 mm Hg SBP and 7 mm Hg DBP.16 The researchers concluded that flaxseed as an intervention is one of the most potent antihypertensive foods yet studied. A review of 11 studies (14 trials) on flaxseed and blood pressure found that supplementing the diet with flaxseeds reduced SBP (-1.77 mm Hg, p=0.04) and DBP (-1.58 mm Hg, p=0.003).17

Flaxseeds are eaten both whole and ground, but given the lack of digestibility of whole seeds, they should be ground so the body can access many of the nutrients.16 Clients can include ground flax in dishes comprising cereal grains such as hot cereal, porridge, or oats or blended into a smoothie for increased fiber and nutrition.

Sunflower Seeds
Sunflower seeds contain not only protein, fiber, monounsaturated fats, vitamin E, manganese, magnesium, selenium, copper, zinc, folate, and iron but also a variety of antioxidants, including the flavonoids heliannone, quercetin, kaempferol, luteolin, and apigenin, and the phenolic acids caffeic, chlorogenic, caffeoylquinic, gallic, protocatechuic, coumaric, ferulic, and sinapic acids.18 Because sunflower oil can be extracted from this seed category, sunflower seeds are considered an oilseed crop.

Several potential health benefits of sunflower seeds have been studied in humans, with primary outcomes being heart health and glycemic management. A small study examining blood cholesterol levels in 22 postmenopausal women with type 2 diabetes found that those who consumed 30 g of sunflower seeds every day for three weeks as part of a healthful diet designed for those with type 2 diabetes experienced reductions in triglycerides (12%, p=0.001), total cholesterol (9%, p=0.073), and LDL cholesterol (9.5%, p=0.607) as well as a significant reduction in HbA1c (3.3%, p=0.017).19

The diet, which followed European and New Zealand dietary guidelines, consisted of 30% total energy from fat (8% saturated fat), 51% carbohydrates, and 17% protein with ≤200 mg dietary cholesterol and 25 to 35 g fiber per day. Participants consuming sunflower seeds also experienced a reduction in HDL cholesterol levels (0.07 mmol/L, p=0.05), suggesting that sunflower seeds may reduce all types of cholesterol.19

There’s also some evidence for a cancer- protective effect. In an observational study of more than 8,000 people, consuming more pumpkin and sunflower seeds was associated with a significantly lower breast cancer risk.20

A typical serving of shelled sunflower seeds is 1 oz, equal to about 1/4 cup or 4 tablespoons (one to two thumb-sized portions). Sunflower seeds are most commonly included in the diet as a snack—especially if they don't need to be shelled—and can be a good option as a grab-and-go snack to bring to a ballgame or any outdoor event. They also can be included in granola or used as a garnish on salads for a crunchy texture.

Sesame Seeds
Sesame seeds, which grow in the tropical and subtropical regions of Asia, Africa, and South America, are rich sources of protein, fiber, vitamins, minerals, and antioxidants such as copper, manganese, and magnesium. Sesame seeds are the most prevalent source of lignans in the diet, being rich in lignans such as sesamin. As with sunflower seeds, sesame seeds are considered an oilseed crop, and sesame oil can be extracted from this seed.

Sesame seeds have been studied in humans for a variety of health benefits, including reduced inflammation and oxidative stress, as well as cardiovascular benefits such as lower cholesterol and blood pressure. One study of 50 participants with osteoarthritis of the knee found that 40 g of sesame seeds daily for two months was associated with significantly lower inflammatory markers of high-sensitivity C-reactive protein (p<0.05) and interleukin-6.21 A 2017 review of meta-analyses on sesame for health concluded that sesame can reduce systolic and diastolic blood pressure (-7.83 mm Hg, p<0.05 and -5.83 mm Hg, p<0.01, respectively).

Researchers hypothesize that many of these benefits are due to the unsaturated fatty acids, fiber, phytosterols, and lignins found in sesame seeds.22

Sesame seeds are the main ingredient in tahini, a paste common in Mediterranean, Middle Eastern, and North African cuisine. In the United States, whole sesame seeds are commonly used as a garnish, but in other countries, they play a major role as flavor in cuisine.

Pumpkin Seeds
One of the most popular seeds, pumpkin seeds are excellent sources of phosphorus, manganese, and magnesium. They also contain monounsaturated fats and omega-6 fatty acids in addition to phytosterols—plant compounds that can help lower LDL cholesterol—and the phytoestrogens secoisolariciresinol and lariciresinol.23,24 Pumpkin is native to South America but now is grown worldwide.

Pumpkin seeds have been used in folk medicine to treat kidney, bladder, and prostate disorders, but science now is supporting those claims as researchers learn more about the properties that support these systems.

For example, pumpkin seeds have been studied for treating symptoms of benign prostatic hyperplasia. A study of 1,431 men consuming 5 g of pumpkin seeds twice daily for 12 months experienced reduced symptoms per the International Prostate Symptom Score (-5.4, a substantial improvement per researchers) and better response to therapy when compared with those taking 1,000 mg pumpkin seed extract twice per day or a placebo.25

Pumpkin seeds are used in a variety of culinary dishes and desserts. They can garnish salads or be ground into sauces for texture and flavor, and be used to garnish muffins and baked goods that contain the flesh of pumpkins.

Hemp Seeds
Hemp is a variety of the Cannabis sativa plant, some strains of which cause psychotropic
effects; however, hemp seeds aren’t intoxicating. Instead, they’re used industrially and for food.

Hemp seeds are soft and mildly nutty in flavor. They’re generally consumed raw, sprinkled on salads, made into energy balls or bars, or added to yogurt or other snacks such as granola.

Hemp seeds contain protein and unsaturated fatty acids and fiber, while hemp seed oil has a 3:1 proportion of omega-6 to omega-3 fatty acids. As a result, hemp seeds may benefit heart health by boosting serum levels of omega-3 fatty acids and increasing fiber intake.26 They also contain vitamin E, phosphorus, potassium, magnesium, calcium, iron, and zinc, as well as antioxidant phenylpropanoid amides, specifically phenylamides and hydroxycinnamic acid amides.26,27

Though there are no recent human studies on the actual consumption of hemp seeds themselves, much has been written about the seeds’ components that may benefit human health, especially the cardiovascular system. For example, hemp seeds contain high levels of arginine, a precursor to nitric oxide, a known vasculature relaxant and blood pressure regulator.26,28

Animal studies have shown that dietary consumption of hemp seeds in rats significantly reduces platelet aggregation; animals fed 5% and 10% ground hemp seed saw significantly higher blood levels of ALA and linoleic acid (p<0.05).29 Another study in rabbits found that after eight weeks, animals fed 10% hemp seed diets had significantly higher blood levels of polyunsaturated fatty acids, particularly 18:3n-6 (gamma-linolenic acid). Researchers also saw that hemp seed feed reduced platelet aggregation, even in animals fed a diet high in saturated fat to raise their cholesterol.30

More research on how hemp seeds affect human health is needed to better understand their potential benefits.

Barriers to Seed Consumption
Though there are many benefits of including a variety of seeds in the diet, there also are some considerations and potential associated health challenges. Food allergens, undigestible carbohydrates, and antinutrients are a few of the reasons clients could have problems consuming seeds. To ensure safety, RDs can educate patients regarding potential challenges they may encounter when enjoying this important food category.

Some seeds are a source of allergens. Peanut, soybean, and tree nut allergies are common. An estimated 2% of US adults have food allergies, and up to 8% of those cases are children.1 It’s also possible to be allergic to flower, vegetable, and fruit seeds. For example, it’s possible to be allergic to poppy seeds, and suffer symptoms such as urticaria, vomiting, swelling of the oral mucosa, and respiratory problems.31 There also are documented cases of oral syndrome after eating sunflower seeds.32 Some people are also allergic or sensitive to wheat or gluten or have celiac disease and therefore can’t consume wheat or wheat varietals, barley, or rye. However, there are plenty of whole grains that people with celiac disease or wheat or gluten allergies and sensitivities can have, including sorghum, teff, millet, amaranth, and buckwheat.

Legumes contain potentially gas-producing carbohydrates in the form of oligosaccharides. Some consumers avoid this category of seeds because of intestinal discomfort; RDs can advise them to use culinary techniques such as soaking or long-cooking. Another alternative is to consume legumes in a different form, such as sprouted or fermented as miso or soy sauce, or extracted to curd, to improve digestibility.1,9

Some seeds, especially legumes, contain a plant defense system referred to as “antinutrients,” which include the protease inhibitors trypsin and chymotrypsin, lectins, and even cyanide-generating compounds (in tropical lima beans).1,9,15 Because of this, trending diets such as Whole30 and Paleo exclude this category of seed. Raw legumes shouldn’t be consumed because of these compounds; however, this would be an unusual way to consume them. Beans are almost always cooked before serving, which removes or deactivates toxic compounds.1

Flaxseeds contain cyanogenic glycosides in addition to phytic acid, a potential chelator that may reduce mineral bioavailability. Animal studies suggest that flax consumption doesn’t alter blood mineral levels, though this likely depends on other antinutrients in the diet and the quantity consumed.15 Quinoa contains bitter saponins, which can be eliminated by soaking and washing the quinoa thoroughly; however, these compounds aren’t inherently dangerous to health. Consumers may inquire about antinutrients in seeds and can be educated that, in the context of a balanced diet, the amount normally consumed in food generally won’t cause health problems.

In the past, guidelines have suggested that people with diverticular disease limit nuts and seeds in the diet for fear they could aggravate the condition and lead to diverticulitis. However, updated research from the American Gastroenterological Association states that it’s unnecessary to advise patients with a history of diverticulitis to avoid foods such as seeds, nuts, and popcorn.33

Finally, seeds are dense in fat and calories, which makes them a good snack or pre- or postworkout fuel. If weight management is a focus for a client, seeds, particularly nuts, should be portioned appropriately as part of a daily calorie goal.

Putting It Into Practice
As long as food allergies and dietary preferences are taken into consideration, consuming a variety of seeds at every meal of the day is a way to increase nutrients in the diet and potentially yield health benefits. RDs can help clients understand that seeds encompass a large variety of foods that are nutritious and may support their health goals. Whether they include grains and cereals, nuts, and/or legumes, all seeds can be part of a healthful dietary pattern.

Educate clients on meeting the DGA by making at least one-half of all daily grain servings whole grains. Clients should consume a variety of protein foods and know that including legumes (eg, beans and peas), nuts, seeds, and soy products could yield additional health benefits if consumed regularly.

Seeds are limited in some amino acids—methionine in beans, lysine and threonine in grains, and lysine in nuts. However, dietitians can educate clients that protein combining to achieve all amino acids within a meal is neither needed nor evidence based. If a variety of foods is present in the diet, the body can assemble the amino acids it needs for various functions.7

— Ginger Hultin, MS, RDN, CSO, is a nutrition and health writer and certified specialist in oncology nutrition based in Seattle. She owns Champagne Nutrition, LLC, a virtual nutrition practice, and is the author of Anti-Inflammatory Diet Meal Prep.

Learning Objectives
After completing this continuing education course, nutrition professionals should be better able to:
1. Distinguish the three classes of seeds and identify which foods are considered seeds.
2. Assess the vegetable, fruit, and flower seeds commonly consumed in the diet.
3. Evaluate the nutrition profiles of commonly consumed seeds.
4. Discuss three potential health benefits of including seeds in the diet.

CPE Monthly Examination

1. Seeds generally contain which nutrients?
a. Vitamin E and folic acid
b. EPA and DHA
c. Vitamin D and calcium
d. Lycopene and choline

2. Which of the following is a type of seed?
a. Chickpeas
b. Avocados
c. Huckleberries
d. Olives

3. Which of the following is not considered
a type of wheat?
a. Einkorn
b. Durum
c. Barley
d. Farro

4. Beriberi is a deficiency of which nutrient?
a. Thiamine
b. Vitamin D
c. Pantothenic acid
d. Alpha-tocopherol

5. Pellagra is a deficiency of which nutrient?
a. CoQ10/ubiquinol
b. Cyanocobalamin
c. Gamma-tocopherol
d. Niacin

6. Phytosterols can cause which of the following health benefits?
a. Increased HDL cholesterol
b. Decreased LDL cholesterol
c. Increased blood methionine
d. Increased triglycerides

7. Hemp comes from what kind of plant?
a. Hackberry (Celtis)
b. Hop (Humulus)
c. Cannabis (not psychotropic)
d. Cannabis (psychotropic)

8. Pumpkin seeds have been used in folk medicine for which of the following?
a. Relieving irritable bowel symptoms
b. Alleviating menopausal symptoms
c. Kidney, bladder, and prostate disorders
d. Cold, flu, and cough

9. Flaxseeds have been studied for improvements in which of the following?
a. Boosting vitamin B1 status in deficient patients
b. Lowering blood pressure in patients with hypertension
c. Reducing inflammation levels in athletes
d. Decreasing breast cancer risk in postmenopausal women

10. Which of the following seeds are safe for a patient with
celiac disease?
a. Corn and barley
b. Rye and amaranth
c. Buckwheat and farro
d. Sorghum and teff


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4. Micronutrient inadequacies in the US population: an overview. Oregon State University, Linus Pauling Institute website. https://lpi.oregonstate.edu/mic/micronutrient-inadequacies/overview. Updated March 2018.

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7. Melina V, Craig W, Levin S. Position of the Academy of Nutrition and Dietetics: vegetarian diets. J Acad Nutr Diet. 2016;116(12):1970-1980.

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10. Guasch-Ferré M, Li J, Hu FB, Salas-Salvadó J, Tobias DK. Effects of walnut consumption on blood lipids and other cardiovascular risk factors: an updated meta-analysis and systematic review of controlled trials. Am J Clin Nutr. 2018;108(1):174-184.

11. Sánchez-Chino X, Jiménez-Martínez C, Dávila-Ortiz G, Álvarez-González I, Madrigal-Bujaidar E. Nutrient and nonnutrient components of legumes, and its chemopreventive activity: a review. Nutr Cancer. 2015;67(3):401-410.

12. Valdivia-López MÁ, Tecante A. Chia (Salvia hispanica): a review of native Mexican seed and its nutritional and functional properties. Adv Food Nutr Res. 2015;75:53-75.

13. Grancieri M, Martino HSD, de Mejia EG. Chia seed (Salvia hispanica L.) as a source of proteins and bioactive peptides with health benefits: a review. Compr Rev Food Sci Food Saf. 2019;18(2):480-499.

14. Toscano LT, Toscano LT, Tavares RL, da Silva CS, Silva AS. Chia induces clinically discrete weight loss and improves lipid profile only in altered previous values. Nutr Hosp. 2015;31(3):1176-1182.

15. Kajla P, Sharma A, Sood DR. Flaxseed — a potential functional food source. J Food Sci Tech. 2015;52(4):1857-1871.

16. Caligiuri SPB, Aukema HM, Ravandi A, Guzman R, Dibrov E, Pierce GN. Flaxseed consumption reduces blood pressure in patients with hypertension by altering circulating oxylipins via an α-linolenic acid-induced inhibition of soluble epoxide hydrolase. Hypertension. 2014;64(1):53-59.

17. Khalesi S, Irwin C, Schubert M. Flaxseed consumption may reduce blood pressure: a systematic review and meta-analysis of controlled trials. J Nutr. 2015;145(4):758-765.

18. Guo S, Ge Y, Jom KN. A review of phytochemistry, metabolite changes, and medicinal uses of the common sunflower seed and sprouts (Helianthus annuus L.). Chem Cent J. 2017;11(1):95.

19. Richmond K, Williams S, Mann J, Brown R, Chisholm A. Markers of cardiovascular risk in postmenopausal women with type 2 diabetes are improved by the daily consumption of almonds or sunflower kernels: a feeding study. ISRN Nutr. 2012;2013:626414.

20. Zaineddin AK, Buck K, Vrieling A, et al. The association between dietary lignans, phytoestrogen-rich foods, and fiber intake and postmenopausal breast cancer risk: a German case-control study. Nutr Cancer. 2012;64(5):652-665.

21. Haghighian MK, Alipoor B, Mahdavi AM, Sadat BE, Jafarabadi MA, Moghaddam A. Effects of sesame seed supplementation on inflammatory factors and oxidative stress biomarkers in patients with knee osteoarthritis. Acta Med Iran. 2015;53(4):207-213.

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