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Help with lipids

  1. Feb 8, 2005 #1
    Hi i've just started grade 11 biology and I am having a problem with one of the homework questions...

    "A 100-g health food bar is advertised as being low in saturated fat. The total
    fat listed as 32.2 g, while polyunsaturates are 1.2 g and monosaturates are
    14.4g. Saturates are 5.0 g. Write a paragraph to explain why you would or would not recommend this bar as a healthy choice."

    I cant make the connection between what ive read in the textbook and this question............ The section was concerning lipids, fatty acids, saturated fatty acids, un saturated fatty acids, glyceerol, triglycerides, phospholipids and steroids....
  2. jcsd
  3. Feb 8, 2005 #2


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    A few things to think about:
    1) With regard to things like elevating LDL/HDL ratios, which are the "bad" fats? Which are "good" fats?
    2) All fats contribute to calories.
    3) What percentage of this bar contains fats? Have you covered nutrition, and what recommendations are for percentage of calories from fats in the diet?
  4. Feb 8, 2005 #3
    Hmmm... We havnt covered calories or nutrition or LDL/HDL ratios we were just told a read a section on lipids (we did a bit on carbs before this) and the teacher outlined this question as being a hard one... like I got all the other ones I was just wondering if I could figure it out myself....

    But i'll try again, sorry for replying so late by the way...

    Well ok basically saturated fats are bad (I dont know why they are bad, I just read it in the text book they are bad for things like the circulatory system) unsaturated fats are good... the total fat is 32.2 g and there are only 5.0 grams of saturated fat in the bar... (I made a mistake in my initial post its monoUNsaturates are 14.4g). 5.0 grams....... doesnt sound so bad? lol I dont know........The question doesnt say anything about calories.....

    So really I dont know if the health bar is good or bad.........
  5. Feb 8, 2005 #4


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    Okay, you're right that the saturated fats are the bad ones. So, you can certainly evaluate the overall claim of whether they are low relative the other fats. Since it doesn't sound like you've covered the material that would really help you really answer the question, my guess (and this is only a guess) is that you should try to use your own judgement about what it means to be healthy. From what it sounds like you've covered on the subject, this is probably meant to be more of a thought question. Either answer may be right as long as you can defend it (there is a more correct answer, but you don't have the information to determine that).
  6. Feb 9, 2005 #5
    Yes, you are absolutely right... today the teacher confirmed that there is no right or wrong answer. You may think there is too much saturated fat, or not enough, we cant evaluate that yet.......

    Thanks a lot anyways
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