A healthy diet should almost always include some fruit, and this is particularly true if you’re suffering from adrenal fatigue. The difficulty arises in choosing the best and most nutritious fruits to eat. Most nutritionists will recommend sticking to low carb fruits where possible as they usually tend to be low in sugar.
This makes a lot of sense if you’re trying to maintain a balanced diet and healthy lifestyle. But how do we measure the sugars in a particular fruit, and which fruits have the lowest amounts?
How To Measure Sugar In Fruits
We don’t actually take a piece of fruit, examine it in the lab, and quantify the grams of sugar in each portion. What actually happens is that we measure the effect that that fruit has on our blood sugar (also called blood glucose) levels. There are two ways to represent this – Glycemic Index (GI) and Glycemic Load (GL). First I’ll explain how these measures work, and at the end of article I have included two tables with the numbers for various fruits.
What Is Glycemic Index?
The Glycemic Index of a food is a numerical unit describing how far eating a food will raise one’s blood sugar level; effectively, it represents how ‘sugary’ the food is. The Glycemic Index uses a scale from 0 to 100, where 100 is pure glucose. A food which has a high GI will cause a large increase in blood sugar, while a food with a lower GI will not have much impact at all.
As a rough basis, mid-50s to mid-60s in a food’s GI is considered average, while 70 and above is considered high. Foods with a GI of less than 55 are considered to have a low glycemic index, and thus will have smaller impact on blood sugar levels. As a general rule of thumb, dried fruits, like many processed foods, have higher GI.
Glycemic Index Vs. Glycemic Load: What’s The Difference?
The main problem with the Glycemic Index is that it does not factor in typical portion sizes. In fact, it standardizes each food to include 50 grams of carbohydrates. This leads to some peculiar distortions. For example, to obtain 50 grams of carbohydrates you would need either 2.8 ounces of a Snickers bar or 35 ounces of pumpkin. It hardly seems fair to compare the two when these portion sizes are so unrealistic!
In 1997, researchers at Harvard University introduced the concept of Glycemic Load with the aim of solving this problem. The Glycemic Load seeks to balance the Glycemic Index by accounting for serving size. Let’s take watermelon’s glycemic index as an example. It has a high GI, as the carbohydrate will increase blood sugar levels rapidly, but it contains a relatively small amount of carbohydrates per serving, meaning that it has a low glycemic load.
A food’s Glycemic Load is calculated directly from its Glycemic Index. We simply take the food’s Glycemic Index, divide it by 100, and multiply it by the grams of carbohydrate (excluding fiber) in a typical serving size. A GL of above 20 is considered high, the 11-19 range is considered average, and below 11 is low.
Let’s look again at watermelon. It has a Glycemic Index of 72, which is relatively high. However, a typical serving size only has 5 grams of carbohydrate. This means we can calculate the Glycemic Load like this: 72/100*5 = 3.6. As you can see from this example, sometimes what is classified as a high glycemic fruit can still be a healthy snack that will barely affect your blood sugar.
However, watermelons are an unusual case, insofar as they have a high Glycemic Index (above 70 is considered high), yet have a low Glycemic Load (below 11 is low). This is not common, as most foods with a high GI will have a correspondingly high GL.
The Glycemic Load Of Fruits
Here are two tables containing the Glycemic Load of various fruits, taken mostly from the American Journal of Clinical Nutrition in 2002 (full version here) and the American Diabetes Association in 2008 (full version here). I have created one table showing the fruits ordered by Glycemic Index, and another showing them ordered by Glycemic Load.
Glycemic Index Chart For Fruits
Remember that a GI of more than 70 is considered high, a GI of 55-70 is considered average, and a GI of below 55 is considered low.
Glycemic Load Chart For Fruits
Remember that a GL of more than 20 is considered high, a GL of 11-19 is considered average, and a GL of below 11 is considered low.
|Fruit||Glycemic Load||Serving Size (grams)|
Glycemic Index And Diabetes
The concept of GI was initially developed to help diabetes patients. It’s important for diabetics and pre-diabetics to pay close attention to their blood glucose fluctuations and insulin levels. However, we can all benefit from paying attention to the carbohydrates we eat.
Here’s what happens to your body when you eat high glycemic foods. Through the process of digestion, carbohydrates are turned into glucose – our body’s essential fuel. Whether we eat a donut or an orange, in the end, both will be converted into glucose. What will be different, though, is how quickly this fuel enters the bloodstream.
Donuts have high GI and GL and will release a lot of glucose all at once. In response, the pancreas will secrete large amounts of insulin. This hormone helps stabilize blood glucose levels by storing the excess in your liver. Yet, if the surge in insulin is too big, too much glucose is removed and blood sugar levels plummet as a result.
This is why you will most likely feel hungry again soon after having eaten a donut. Overconsumption of processed foods may even make us feel sluggish and demotivated, while consuming certain fruits can make you feel happy.
A Low-Glycemic Diet Could Help Manage Your Weight And Energy Levels
A diet consisting of high-GI and GL foods produces large spikes and drops in blood sugar, ultimately leading to weight gain and fatigue. The opposite is also true – if you maintain more stable blood glucose levels, you will feel more energetic. Low GI and GL foods usually contain a lot of fiber that slows down digestion and supports blood sugar stability.
When we eat high-fiber foods – like many fruits – glucose is released more gradually into the bloodstream. We feel full for longer, eat less, and burn fat instead of storing it. So in the end, it makes a huge difference whether you get your carbohydrates from a donut or an orange.
This has implications for more than just your weight or looks. Studies have shown that people on high GL diets have a higher risk of diabetes and heart disease. It’s important to note that high glycemic foods are usually also highly processed, high in calories, and low in vitamins and minerals. So there are many factors to consider.
Should You Avoid High GI And GL Fruits?
Bear in mind that a high GI and GL does not necessarily mean that fruits are unhealthy and should be avoided. Compared to refined carbs, whole foods are a much more nutritious option. In fact, fruits are some of the healthiest carbohydrates a person can consume. They contain lots of antioxidants and vitamins, and the sugar they contain is paired with lots of fiber so is less likely to spike your blood sugar.
However, if you’re following a low-carb diet or worried about your blood sugar, you may use the above tables to select fruits that are just as rich in vitamins and minerals but low on carbs. Generally, high GI fruits have more total carbohydrates.
Create Your Own Healthy Eating Plan
Are you looking for more healthy eating tips? In The Adrenal Fatigue Solution, Dr. Wood and I lay out a healthy eating plan with lists for the foods that you should eat and avoid. I have also included lots of super-nutritious recipes that will help to boost your energy levels.