Which rice is best for a diabetic? – Glycemic Index analysis (Part 1)

*This is part 1 of a 3-part series on the Glycemic Indices of various Indian foods*

Is there any rice that is good for a diabetic person? Is parboiled rice better than raw rice? What effect does ponni, sona masuri, basmati etc have on your sugar levels?

To find out, let us do a deep dive and let the numbers do the talking…

First, the basics…

What is Glycemic Index?

The glycemic index (GI) is a physiological ranking, 0 to 100, used to reflect how a carbohydrate-containing food causes an increase in blood sugar (glucose) levels.

If your food has a GI of below 55, it is considered a low-GI food, between 55-70 is medium GI and above 70 considered high GI.

For a detailed background video on GI, look at this video by my favorite Italian PhD nutritionist. His Youtube channel, Nutrition Steps is a boon for society!!

Where do you find the Glycemic Index numbers?

For standard numbers, I usually go to University of Sydney – website. They have a huge compilation of glycemic index results from around the world. You can click on any result and know exactly the details of the experiment too. It is super cool!!

My other go-to resources – Harvard health and a list by Dr. Rob Thompson, who has written great books on this topic.

Before moving forward, let us address any concerns with GI

Even though I love using the Glycemic Index as a starting point for my research, it is still not a perfect metric. Why, you ask?

When scientists try to duplicate the experiments, there is sometimes variability of up to 20%. Blood insulin response as tested by insulin index and HbA1c, a measure of longer term glucose control, had the largest effect, accounting for 15% and 16% of the variability, respectively. That suggests glycemic index values are influenced by an individual’s metabolic responses to food.

https://www.nutritionletter.tufts.edu/issues/12_12/current-articles/Why-You-Cant-Rely-on-the-Glycemic-Index-for-Healthy-Eating_2064-1.html

So, while you may not get super tight answers using just GI alone, I think you can use it in your toolkit to help you eat better. I think that GI along with common sense + parameters like understanding protein, fiber content, etc can give you some idea on where to start controlling your sugar as a diabetic.

Which rice has low GI?

Will rice have a single GI result? No, of course not!! There are so many varieties of rice, each with different properties, and hence each with different results.

A study found that the GI of rice ranges from a low of 48 to a high of 92, with an average of 64. The GI of rice depends on the type of rice. This is such a large range. Hmmm…is there a clue to know if the rice will have high GI or not? Funny, you should ask….

High amylose content => Low GI

In order to predict which rice will have high GI, you must know how much amylose the rice contains.

There is clear evidence that rice that is high in amylose content has a lower Glycemic Index number. More research evidence here and here.

Are you wondering, what amylose is? It is a simple concept actually. Basically, there are two types of starch in rice: amylose and amylopectin.

Amylose is a long, straight starch molecule that does not gelatinize during cooking. Rice with a high amylose content (25-30%) tends to cook firm and dry, whereas rice with a intermediate amylose content (20-25%) tends to be softer and stickier and rice with a low amylose content (<20%) is generally quite soft and sticky. Waxy rice has a zero amylose content and is often referred to as sticky rice. Amylose also hardens more when cool.

Amylopectin, on the other hand, is a highly branched molecule that makes the rice sticky when it’s released from the grain during cooking.
Medium grain rice has more amylopectin, making it a good candidate for risottos, salads and rice pudding. Short grain rice has even more amylopectin and little to no amylose. Then there’s glutinous rice, which is very sticky when cooked, with the highest amount of amylopectin and no amylose.

So, when it comes to GI/ diabetics:

Amylose= good, Amylopectin = bad!!

Sometimes, their names can be confusing. Here’s an easy way (mind trick) to remember it. Just think:

Jam uses pectin => pectin is sticky => more sticky is bad => amylopectin = bad!!

While high amylose is a strong indicator of GI, there are other factors that also come in play. For eg:

Which rice varieties have low, medium and high amylose?

Based on a global study of rice varieties, it was found that consumers in Thailand, Japan, parts of China and Vietnam prefer waxy or sticky rice (low Amylose). Rice with intermediate amylose content is preferred in Iran, Pakistan, Malaysia and many states in India. High amylose varieties are popular in Myanmar, Sri Lanka, some states in India, Ghana, Senegal, etc.

Check out the regions in Asia that uses high amylose grain –

1. Kerala + Sri Lanka
2. North east parts bordering Myanmar

Remember the high amylose rice have around 30% amylase. Guess what? The traditional rice varieties of Sri Lanka like Suwendel, Rathel, Heenati all have around 30% amylase. In fact, Sri Lankans are lamenting that the traditional, superior varieties are slowly losing popularity to newer, fast cooking, high GI strains. Several Basmati varieties has amylose levels around 30% as well.

Median GI of Various Rice varieties:

Srilankan Rice Varieties (1)

• Kalu Heenati 56.3
• Wada Heenati 52.5
• RathKaral 62
• Mada thawalu 64

*Note – Not all red rice varieties automatically have low-medium GI. Just because it is red, does not mean low GI. However, It can have other great parameters like iron content, fiber etc.

Kerala Varieties (2)

• Njavara 74.8
• Jyothi 73.1

*I was hoping to find out which strain of rice in Kerala gave low GI values, but I was unable to find good research on it. Some websites tout Rose Matta rice as extremely low GI, but give no evidence/ studies to back it up. I would love to see more studies published focusing on the traditional Kerala rice varieties.*

Traditional Tamil and Andhra Varieties (3)

• Sona Masuri 72
• Ponni 70
• Surti Kolam 77

As you can see, these popular varieties from Tamil Nadu and Andhra Pradesh have high GI, and bred more based on taste, rather than its impact on health.

Thai Jasmine Rice (4)

• Jasmine Rice 96- 116

It is easy to confuse Basmati and Thai. They are both ‘fragrant’ rice. But, do not mix them up. Jasmine rice has very high GI due to lower amylose content.

Basmati Rice (5)

• Basmati Rice GI is typically between 55-65

*There is no specific data, because there are so many varieties and hybrids that come under the umbrella of Basmathi rice but check out link for results from different brands.*

Black Rice (6)

• Black Rice/ Kavuni Arisi 42

I am personally such a fan of this rice, which is brilliant all around the nutrition spectrum (Superior iron, calcium, antioxidants, etc). Check out my post on black rice!! My only wish is that it gets less expensive.

Parboiled Rice (7)

• Parboiled Rice Range 38- 72

Parboiling automatically does not mean lower GI. It depends on the type of grain that is being parboiled and the level of parboiling. But, typically, having the parboiled version seems to be nutritionally superior and lower in GI compared to the raw form.

For eg, in this study, they found that the GI of a certain type of long grain white rice was 83, but the parboiled version drops the GI to 67.

Conclusion

So, how does the rice measurements compare to eating roti? According to a study published by the Madras Diabetes Research Foundation, mean GI for whole wheat flour roti was 45.1. Only black rice seems to beat that value.

So, which rice is good for a diabetic? Eating the correct rice is like a sliding scale. If you are worried about your rising sugar levels, stick to the bottom of the list with low GI.

• Sticky rice, glutinous rice, Jasmine rice, etc – Super High GI values
• Ponni, Sona Masuri, Njavara – High GI values
• Sri Lankan Rice (specific varieties), Basmati, Certain Parboiled varieties – Medium GI
• Black Rice – Low GI

Not a 100% rule – but in most cases – The whiter/ the more polished/more sticky a rice is, generally the GI seems higher. The more colored/ more fiber/more separate grains the rice has, the GI seems lower.

One more thing – adding fiber (bran, veggies) dramatically reduces the GI of the entire meal. I will explain more in Part 2 and Part 3 of this series.

Don’t forget to tune in for Part 2 explaining the GI of tiffins like Upma, Pongal etc and Part 3 looking at other whole grains like barley, ragi, etc.

Which will be good and which will be bad for your sugar levels? The answer may surprise you. So, stay tuned!!

Also Read:

• WHICH SOUTH INDIAN BREAKFAST IS MOST LIKELY TO RAISE YOUR SUGAR? (GI ANALYSIS -PART 2)
• HOW TO EAT A LOW GLYCEMIC DIET AS AN INDIAN VEGETARIAN (PART 3)

Other References

Amylose content of Rice grown around Tiruchirapalli area

Disclaimer

I am not a nutritionist/nurse/doctor. I just study numbers and report them. Consult your doctor before making any major changes to your diet.