Olive, coconut, peanut, avocado, walnut … there are many plant oils to choose from today, and they’re generally considered healthy options—especially if they’re cold-pressed and unrefined. But is there more to know? Take our quiz to find out.
1. Which of these parts of a plant are most often used to make oils?
2. How many calories does a tablespoon of most plant oils contain?
3. Olive oil is considered to be beneficial because:
a) It contains omega-3 fat, the plant version of the healthy fat found in fish.
b) It is anti-inflammatory and rich in antioxidants.
c) Both of the above
Olives, a staple in Mediterranean cuisine, were first cultivated more than 5,000 years ago.
4. The healthiest type of olive oil is labeled:
a) Pure olive oil
b) Virgin olive oil
c) Extra-virgin olive oil
5. Which of these is richest in omega-3 fats?
a) Walnut oil
b) Flaxseed oil
c) Chia seed oil
d) Hemp seed oil
6. Canola oil is the same thing as rapeseed oil.
7. Which of these oils should not be used for high-heat cooking?
a) Flaxseed oil
b) Coconut oil
c) Peanut oil
8. Refined oils are treated with:
a) High heat
b) Chemical solvents
c) Bleaching agents
d) All of the above
1. d) Seeds. Although we may not think of corn, coconuts, olives, nuts, or soybeans as seeds, they are in botanical terms, and the seeds contain small amounts of oil.
2. c) Most oils contain about 120 calories per tablespoon, although some can contain a few more. Check Nutrition Facts on the label.
3. b) Studies show that olive oil is anti-inflammatory, rich in antioxidants, and linked with good health and longevity in cultures where it is a staple. But it is not a good source of omega-3 fats.
4. c) Extra-virgin olive oil is cold-pressed, unrefined, richest in flavor, and highest in beneficial nutrients. Virgin olive oil contains lower levels of nutrients. “Pure” olive oil may contain refined as well as virgin olive oil, and delivers the lowest levels of nutrients.
5. b) ) Flaxseed oil is the richest in omega-3 fats, followed by chia seed oil, walnut oil, and hemp seed oil, in that order.
6. b) Canola oil comes from a plant that was bred from the rapeseed plant to reduce levels of erucic acid and glucosinolates, undesirable ingredients that were naturally found in the parent rapeseed plant, so the two are not identical. Most canola comes from genetically modified plants, although organic canola is non-GMO. There are different perspectives about whether or not canola is a healthy oil.
7. a) Flaxseed oil breaks down with heat and should not be used for cooking at all. It can be used in salad dressings, or added to foods after they’re cooked. Both coconut and peanut oils withstand heat well.
8. d) High heat and chemicals are used to extract, and then bleach and deodorize refined plant oils, destroying nutrients and changing the composition of the fat. The best way to tell if a plant oil has been refined is to look for information on the label. If it isn’t clear, ask the manufacturer how the oil was made.