Test glucose content

[deleted-83937]

Hi,

I would like to test glucose content of different variety of rice. I am thinking of using brown rice, parboiled rice and Basmathi rice. Which is the best way of doing this. I looked at https://www.sciencebuddies.org/science- ... p049.shtml

How can I modify the above experiment to use for my rice project?

Any help is appreciated.

Regards

Vish

[deleted-71536]

Hi Vish,

You absolutely can modify the "How Sweet It Is" project to measure the glucose contents of different varieties of rice. Keep in mind that the differences in glucose content *could* be very small, so they may or may not be detectable with the test strips. Also keep in mind that the test strips only work in liquids, so you will need to find a way to liquefy your rice. I suggest cooking the rice (with the same ratio of water to rice for each type), using a blender or food processor to mash up the cooked rice, and then diluting the rice further (again, the same amount for each type) to create a liquid mixture.

All varieties of rice are based on carbohydrates. Do you have any predictions for the differences in glucose content based on your background research? Do the different varieties of rice have different sugar totals listed on their nutrition facts?

I hope this helps! Please post again (in this same thread) if you have more questions.

Heather

[deleted-83937]

Hi Heather,

Happy New Year!

Thanks for your response. I am planning to test Brown Rice, Basmati and long grain rice. Based on research I think brown rice will have less Carb. The basmati and long grain show zero grams of sugar whereas the brown rice shows 1 gm. Does the level of Carb matters or the sugar content matters. I was surprised to see 1 gm of sugar in the nutritional information for brown rice. I had earlier planned to do Glycemic Index but could not get volunteers to test blood sugar so doing the glucose project. My main concern is to find which rice is best for people with Diabetics. With this info do you think the glucose test is the right way to proceed?

[deleted-71536]

Hi Vish,

Happy New Year to you, too!

Thanks for providing the additional information. It is interesting that you want to relate the amount of sugar in the rice to its effect on people with diabetes. I think that glycemic index is a much more accurate way to measure this, as different carbohydrates (and other foods) can still increase blood glucose. Check out this information from the American Diabetes Association: http://www.diabetes.org/diabetes-basics/diabetes-myths/, http://www.diabetes.org/food-and-fitnes ... -counting/

Your measurement will only be detecting glucose. If you are interested in the total amount of carbohydrates in your rice, you might try using a different test. Here is some information for testing total carbohydrates in food: http://people.umass.edu/~mcclemen/581Carbohydrates.html. This is a much more complicated analysis, so you may not want to go that route. But you do need to understand that it is not just glucose itself that causes blood glucose to rise after eating. I do think that glycemic index is the best way to directly test what you are interested in.

Here is the Wikipedia article regarding the glycemic index: http://en.wikipedia.org/wiki/Glycemic_index. Although Wikipedia is not considered a reliable resource, it's a good starting place and the bibliography usually has a lot of great resources.

I hope I have not discouraged you. Your project idea is still interesting in its own right. You could test the glucose content of the different kinds of rice, and still talk about how that relates to the total amount of carbohydrate in each type. The American Diabetes Association points to the total carbohydrate as a risk factor, over any other measure. But it is interesting that brown rice contains more sugar, whereas the other kinds of rice have more starch.

If you wanted to change your project a bit, you might consider testing the glucose content of different types of food with different (known) glycemic indices. Then you could see whether glucose content and glycemic index are related, and how.

Please post again if you have more questions!

Heather

[deleted-83937]

Hi Heather,

Thanks for your reply. I am thinking of doing the Glycemic Index. My parents are willing to volunteer. I am not sure with just 2 people it will be a good data. I am trying to get one another volunteer.

Meanwhile, I was planning to cook the rice the same way and have the volunteer eat it first thing in the morning and test the blood sugar after 2 hours.

Regards
Vish

[deleted-71536]

Hi Vish,

I think looking at glycemic index will make your results more applicable to diabetes.

Who will be drawing the blood? Since you are thinking about working with human subjects, you should be aware that there are guidelines you will need to follow. Here is some information about that: https://www.sciencebuddies.org/science- ... ects.shtml

A sample size of two is very small. It would be good to get at least 5-10 volunteers, if possible. I assume that each person will be eating all three types of rice, each type on a different day.

I think it is also important to look at baseline blood sugar (before the rice is eaten). While it is good that you plan to have them eat the rice first thing in the morning, it's important to note that each person may be starting with a different blood sugar level. Since you are interested in the elevation of blood sugar, it would be important to measure the starting value each time.

Best,
Heather

[deleted-83937]

Hi Heather,

Thanks for your reply. I have now 4 people volunteer for the project. I was planning to measure with a known food the first time on day one. Then test the different variety of carbs. I am considering if I should just do rice or carbs. The people who volunteer also eat noodles so they want to know about that food as well.

For testing for carbs, I would first test the blood sugar before they eat the food and then after 2 hours as per your suggestion. Planning to do this 3 times for the same food on different days and continue with 3 -4 different carbs( Rice and noodles). Feeling bad that I have to poke them multiple times.

My father is going to help me in the testing.

I also submitted a SRC approval to the local Science Fair organization and waiting for approval.

Please let me know if I need anything else.

Regards
Vish

[deleted-71536]

Hi Vish,

Sounds great! The only other suggestion I have is that you test the different foods in a random order. In other words, mix up the order in which each subject eats the different foods.

Otherwise, it sounds like you are on the right track. Let me know if you have any more questions along the way.

Heather

[deleted-83937]

Thanks Heather.

I have these foods selected for testing.

Foods that we will Test: ( 50 gms of test food and 250 ml of water)
White rice
Pasta
Mashed potatoes
Brown rice
Corn

Let me know if you have any suggestions.

Planning to do the reference food ie White bread starting this Saturday. For this I had planned to test the blood glucose before the start of the test, and at 1 hour after the volunteers had the food and again at the end of 2 hours so I can get an AUC for the reference food. I suppose I might have to take the average AUC of the reference food of the volunteers to use later for calculating the GI of test food.

I looked at how it is done at http://www.nature.com/ejcn/journal/v61/ ... gure-title

Regards
Vish

[deleted-71536]

Hi Vish,

Looks like you are on your way! Good job locating a scientific reference for your methods.

Note that the article states "The test food and reference food (usually 50 g glucose) must contain the same amount of available carbohydrate." It is important to look at the available carbohydrate in the food. In other words, the technical way to standardize the measurements would be to compare foods at 50g of carbohydrate (not 50g of the food itself). However, as long as you are consistent with your measurements, it could still work.

From what I can tell, you take the AUC for your reference food (just until it hits the baseline), and then you report the glycemic index as a percentage of the reference AUC. So you don't really need an average. The idea is to use each person as his/her own control.

Keep up the good work, and please continue to keep me posted on your progress!

Heather

[deleted-83937]

Hi Heather,

Thanks for your reply. How do I measure 50 gms of carb in a food. Do I use the Nutritional info.

Regards

Vish

[deleted-71536]

Yes, you can use the food label to determine the number of carbs. Remember that the label tells you the grams of carbs per serving, so you'll need to look at the serving size and multiply (or divide) accordingly. The American Diabetes Association explains it at the bottom of this page: http://www.diabetes.org/food-and-fitnes ... -counting/

You might have a harder time with fresh corn, but canned corn should have a nutritional label you can use.

Remember to have your subjects fast (not eat for 12 hours) before each test, so that the only thing in their stomach is the food and water you give them. The easiest way to do this is to have them do the test first thing in the morning, before they eat breakfast. No juice or coffee before the test, either!

Heather

[deleted-83937]

Thanks Heather,

I was about to post this link which i found

http://www.diabetesnet.com/food-diabete ... bohydrates

Regards

Vish

[deleted-71536]

Excellent! You're on your way.

[deleted-83937]

Thanks Heather.

I did the reference food and one test food during the weekend. Seems each individual has a lot of variation for the same food. I am still wondering how the GI would be common across different people.

Thanks once again.

I will keep you posted.

Regards
Vish

[deleted-71536]

Hi Vish,

Individual variation is the very reason that we need multiple test subjects. It's also why each person will serve as his/her own control, since it would not make sense to compare one person's test food to another person's control. The reported GI for each type of food is likely an average from many different people.

Keep in mind that other factors will affect the GI. As I mentioned, each person needs to be fasted for at least 12 hours and not consume anything before the test. Things like hormone levels (especially of insulin and glucagon) can affect each person's reaction, as well as what the person ate the day before each test. These are variables you cannot control, so you can talk about them in the discussion of your results.

It will be interesting to see if there is at least a consistent trend for GI with the different test foods. Please keep me posted as you collect more data! Once you have the data, I would be happy to help you figure out the best way to present everything.

Best,
Heather

[deleted-83937]

Hi Heather,

Thanks for the feedback. I will share the info and be happy to get your advice on how to represent the data.

Regards
Vish

[deleted-83937]

Hi Heather,

I wanted to share one thing that I noticed in one of the volunteers blood glucose. It constantly shows a decrease after eating food and only after 2 hours he shows an increase. Also I am trying to measure just the area under the curve starting from baseline( fasting food value) and the value at end of 2 hours. Sometimes I notice the volunteers blood glucose does not come back to the fasting level within 2 hours. So I just the area by extending the curve to the baseline.

Also I am plotting each person data for different food in a single graph for my lab work, using different color for each food. And then plan to calculate the GI using the individual person AUC for different food/ AUC of Bread multiplied by 100.

Once I done calculating the GI of different food for each person, I would put that in another graph to see the variations for same food among the different volunteers.

Will keep you posted.

Regards
Vish

[deleted-71536]

Hi Vish,

Thank you for the update! Everything sounds great. It is very interesting that one of your volunteers has an initial dip in blood glucose. I wonder if he or she has a very high insulin response.

It sounds like you are doing the right thing to calculate the area under the curve when the blood glucose has not reached baseline by 2 hours. Just extend the graph straight down, rather than assuming a continuation of the curve.

Looking forward to more updates!

Heather

[deleted-83937]

Hi Heather,

Thanks

I do have a question on plotting the graph. The measure of blood glucose meter is in mg/dl where as I see most of the AUC using mmol/l. DO I need to re-plot the graph after converting to mmol/l.

For now the values for the AUC reading looks like this

1.4740 mg/dl . min
2.2590 mg/dl.min



Regards
Vish

[deleted-71536]

Hi Vish,

Since the glycemic index is calculated as a percentage of the reference AUC, the most important thing is that your test AUC and reference AUC are in the same units as each other. Since you measured everything with the same glucose meter, that will work for you. So the short answer is no, you do not need to re-plot your graphs.

If you want your results to be comparable to other studies, you could convert mg/dl to mmol/l. To convert from mg of glucose to to mmol, you will use the molecular mass (g/mol) of glucose (by adding the masses of its component elements from the periodic table). To convert from deciliters of solution to liters of solution, note that there are 10 deciliters in a liter.

Since both of these conversions would be the same for every measurement you did - since glucose does not change its molecular mass, and there are always 10 deciliters in a liter - doing the conversion would not change the shape of your graph. You could keep your graphs and just report the converted values for reference in a separate table.

Heather

[deleted-83937]

Thanks Heather.

I will keep the graph as it is. I am wondering if I got to take 2 more trials for the same food or 1 test for each food with 4 volunteer is good?

Regards

Vish

[deleted-71536]

Hi Vish,

Since you are measuring GI for four people on multiple foods, I think your experimental design is good. Doing multiple trials on the same individuals could help you account for variation within individuals, but I'm not sure that's the most important thing here. Honestly, I think finding more volunteers would help more than adding trials for the same volunteers. So you can stick with what you have, or see whether you can convince anyone else to participate in your study.

Keep me posted!

Heather

[deleted-83937]

Thanks Heather.

I will try to see if I can find new volunteer. Will keep you posted. Also as I am doing the test I am also making a draft of the content I am planning to use on my board. If you want to review let me know what is the best way to share it.

Regards

Vish

[deleted-71536]

Hi Vish,

Sounds great! If you are able to put the materials for your board into pdf or jpeg format, you can upload it as an attachement (or multiple attachments, depending on the size) right here on this forum. I would be happy to review them for you.

Heather

[deleted-83937]

Thanks Heather. I am working on this and will have most of it done by this weekend.

Meanwhile this was some of the title for the project that me and my partner discussed with our volunteers. let me know what should be the best or suggest us one.

1. Prevent Diabetes. Does the type of carb matter?

2. Does the type of carbohydrate really matter!?

3. What type of carbohydrate harm us the most?

4. How can we prevent diabetic by selecting different carbohydrate.?

5. Should every one know there own Glycemic index for different carbohydrate?

[deleted-71536]

Hi Vish,

I'm glad things are coming together!

It's important to make sure your title reflects what you actually studied. You are not looking at a way to prevent diabetes, but rather what carbohydrates might be better for a diabetic to consume when trying to control his or her blood sugar. I would also avoid implying that carbohydrates harm us, as they are essential macromolecules needed for nutrition!

How about something like the following:
1. Are there "good" carbs? The effects of different carbohydrate foods on glycemic index.
2. How do different carbohydrate foods affect blood sugar?

I hope this helps!

Heather

[deleted-83937]

Hi Heather,

Thanks for your suggestion. I will discuss this with my partner.

Also when you get a chance pls see the pdf and let us know if it looks ok.

We would like to mention you as our mentor. Please send what info we can add to the project as we wanted to give credit to you for your help.

Regards

Vish

[deleted-71536]

Hi Vish,

Your presentation looks great! I do think you should include the graph to show how you calculated the AUC, since that is easier to explain with a figure.

Overall, you did a very thorough job and you should be very proud.

I am happy to help, and you do not need to give me credit. My name is Heather Liwanag, and you can just say that I am an Expert for Science Buddies.

I hope your presentation goes well!

Heather

[deleted-83937]

Thank you Heather. I will keep you posted on how our presentation goes. Let me know if you have any other suggestions.

Vish