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Olive or canola? Pick one based on your health needs
By Karen Collins, R.D.
Registered Dietitian
Special to MSNBC.com
Updated: 12:57 p.m. ET April 29, 2005
Many different cooking and salad oils are available today. Fortunately, there are a number of healthful options, so you should pick one or several of these based on how you intend to use it and your particular health concerns.
The newest cooking and salad oil, Enova oil, is made from soybean and canola oils. Its manufacturer claims it helps reduce body fat.
While fats and oils normally have a chemical structure consisting of a “backbone” with three fatty acid arms on it, this oil is specially processed, so that most of the fat is composed of a backbone and two arms, also known as a diacylglycerol (DAG).
This type of oil is digested and absorbed just like other fats, but the body handles it differently because of its unique structure. Instead of circulating through the body, DAGs seem to go directly to the liver to be burned for energy.
While one brief study has shown that DAG oil increases fat burning, the rate of increase would make a difference of only three to four pounds a year. Based on the results of four- and six-month studies, substituting one to three tablespoons of Enova oil for the oil or margarine you now use might produce four to six pounds of weight loss per year. (Note that this possible weight loss depends on replacing your current oil with Enova, not adding it to what oils you currently eat.)
If you substitute an average of only one teaspoon of this oil a day, weight loss for the year might be one pound. Because the possible weight loss is so slight, Enova is unlikely to influence weight management much, although it may help prevent the small yearly gains many adults experience.
And, contrary to some sources that suggest DAG oil may lower blood triglycerides, studies do not consistently show that it has an effect on blood triglycerides or cholesterol. Results are not completely positive about its effect on blood sugar either.
Different types of fat
Like Enova oil, canola oil is exceptionally low in cholesterol-raising saturated fat. Canola oil contains more monounsaturated fat, however, while Enova oil has more polyunsaturated fat.
Although both types of fat are heart-healthy, research suggests that polyunsaturated fats are less stable and can leave cells more vulnerable to damaging free radicals. Cell damage from free radicals can lead to cancer, age-related vision loss and other health problems. The predominantly monounsaturated fat in canola oil is more stable.
Another advantage of canola oil is that about one-third of its polyunsaturated fat is omega-3 fat, the healthful fat found in salmon and other fatty fish. Experts say that increasing the proportion of omega-3 to omega-6 fat (the other type of polyunsaturated fat) in your diet could help prevent heart disease, cancer and other health problems.
Because Enova oil supplies less omega-3 fat, the omega-3 to omega-6 balance is more favorable in canola oil.
Don't forget olive oil
Olive oil is another healthy choice. Although its saturated fat content is slightly higher, it remains under two grams per tablespoon. And olive oil contains even more of the highly stable monounsaturated fat in canola oil.
Although it has considerably less omega-3 fat than canola oil, olive oil offers natural phytochemicals such as phenols, flavonoids and lignans, which are powerful antioxidants that seem to inhibit the development of some cancers.
Squalene, another phytochemical in olive oil, may inhibit cell changes and the activity of enzymes that can result in cancer. Research has yet to clearly show how many phytochemicals are in canola oil or if they remain in Enova oil after processing.
Enova, canola and olive oils are all healthy choices, each with their own advantages. But remember to use them in moderation. Although we need the fatty acids they provide for good health, they all contain 120 calories per tablespoon.更多精彩文章及讨论，请光临枫下论坛 rolia.net
Olive or canola? Pick one based on your health needs
By Karen Collins, R.D.
Registered Dietitian
Special to MSNBC.com
Updated: 12:57 p.m. ET April 29, 2005
Many different cooking and salad oils are available today. Fortunately, there are a number of healthful options, so you should pick one or several of these based on how you intend to use it and your particular health concerns.
The newest cooking and salad oil, Enova oil, is made from soybean and canola oils. Its manufacturer claims it helps reduce body fat.
While fats and oils normally have a chemical structure consisting of a “backbone” with three fatty acid arms on it, this oil is specially processed, so that most of the fat is composed of a backbone and two arms, also known as a diacylglycerol (DAG).
This type of oil is digested and absorbed just like other fats, but the body handles it differently because of its unique structure. Instead of circulating through the body, DAGs seem to go directly to the liver to be burned for energy.
While one brief study has shown that DAG oil increases fat burning, the rate of increase would make a difference of only three to four pounds a year. Based on the results of four- and six-month studies, substituting one to three tablespoons of Enova oil for the oil or margarine you now use might produce four to six pounds of weight loss per year. (Note that this possible weight loss depends on replacing your current oil with Enova, not adding it to what oils you currently eat.)
If you substitute an average of only one teaspoon of this oil a day, weight loss for the year might be one pound. Because the possible weight loss is so slight, Enova is unlikely to influence weight management much, although it may help prevent the small yearly gains many adults experience.
And, contrary to some sources that suggest DAG oil may lower blood triglycerides, studies do not consistently show that it has an effect on blood triglycerides or cholesterol. Results are not completely positive about its effect on blood sugar either.
Different types of fat
Like Enova oil, canola oil is exceptionally low in cholesterol-raising saturated fat. Canola oil contains more monounsaturated fat, however, while Enova oil has more polyunsaturated fat.
Although both types of fat are heart-healthy, research suggests that polyunsaturated fats are less stable and can leave cells more vulnerable to damaging free radicals. Cell damage from free radicals can lead to cancer, age-related vision loss and other health problems. The predominantly monounsaturated fat in canola oil is more stable.
Another advantage of canola oil is that about one-third of its polyunsaturated fat is omega-3 fat, the healthful fat found in salmon and other fatty fish. Experts say that increasing the proportion of omega-3 to omega-6 fat (the other type of polyunsaturated fat) in your diet could help prevent heart disease, cancer and other health problems.
Because Enova oil supplies less omega-3 fat, the omega-3 to omega-6 balance is more favorable in canola oil.
Don't forget olive oil
Olive oil is another healthy choice. Although its saturated fat content is slightly higher, it remains under two grams per tablespoon. And olive oil contains even more of the highly stable monounsaturated fat in canola oil.
Although it has considerably less omega-3 fat than canola oil, olive oil offers natural phytochemicals such as phenols, flavonoids and lignans, which are powerful antioxidants that seem to inhibit the development of some cancers.
Squalene, another phytochemical in olive oil, may inhibit cell changes and the activity of enzymes that can result in cancer. Research has yet to clearly show how many phytochemicals are in canola oil or if they remain in Enova oil after processing.
Enova, canola and olive oils are all healthy choices, each with their own advantages. But remember to use them in moderation. Although we need the fatty acids they provide for good health, they all contain 120 calories per tablespoon.更多精彩文章及讨论，请光临枫下论坛 rolia.net
