Generally speaking, fruit is good for our body. It comes from nature and contains vitamins, minerals, antioxidants, water, and fiber. All of the good stuff our body needs for optimal health! However, if excess body fat, diabetes or pre-diabetes, or cravings for sweets throughout the day is a problem for you, then there is a reason to limit fruit and make wise choices when you do enjoy it. I’m going to share with you why I encourage you to select low-sugar fruits mindfully instead of diving into the fruit bowl anytime of the day.
Fruit contains both glucose, fructose, and sucrose, a 1:1 ratio of glucose and fructose. Glucose and fructose are two monosaccharides that are metabolized differently by the body whereas sucrose is a disaccharide that is metabolized similarly to fructose. Glucose is metabolized to first provide immediate energy to the body and then all excess is stored as glycogen in the muscles and liver. Once storage is filled, it is stored as fat in adipose tissue. One key point to remember is that glucose triggers the release of insulin because insulin is required to move glucose from the bloodstream into the cell for energy production and storage (via insulin-sensitive glucose transporters). Fructose, on the other hand, is sent to the liver for metabolism. Too much fructose leads to synthesis of triglyceride synthesis and thus storage in adipose tissue. Remember the effect of glucose on insulin? Fructose does not trigger an insulin release and therefore does not contribute to satiety signals in the body. Bottom line: glucose raises blood sugar levels, fructose does not. Glucose assists in “feeding” the cells thus signaling the brain to stop eating, fructose does not.
So where am I going with all of this glucose and fructose talk? When we’re making choices on fruit, it is important to understand overall carbohydrate content and how much of that carbohydrate is sugar. The remaining carbohydrate content of a food is based in its fiber, which is also important, but does not contribute to overall levels of sugar in the food. Recognizing fruits that are relatively low in sugar is key to selecting fruits. These include (based on a 100 gram serving that contains <10 grams of total sugar) avocado, lime, lemon, raspberries, blueberries, strawberries, grapefruit, blackberries, cantaloupe, sour cherries, guava, apricot, figs, nectarine, orange, papaya, peach, plum, starfruit, tangerine, tomato, and watermelon. This is a large group of fruits to choose from so you need to never feel deprived. Additionally, 100 grams looks different for each fruit so do a little research and learn what 100 grams of figs looks like versus 100 grams of cantaloupe. All other fruits not listed contained more than 10 grams of total sugar for a 100 gram serving.
Now, to plug all of this fruitful information into your diet! Remember that 50% of your plate should consist of vegetables and low-sugar fruits. Once you’ve made at least half of that vegetables, then you can fill the other half with low-sugar fruit. If your goal is a low-carbohyrate diet then you would skip the fruit altogether and just nosh on your vegetables. If you’ve just finished a workout, enjoy 1 cup of fruit with a generous serving of protein. The body will quickly use the fruit sugar to refill glycogen stores with little or none remaining for storage in adipose tissue. As a general rule of thumb, I encourage you to be generous on vegetables first and then enjoy a maximum of 2 cups of fruit per day. The logic behind this is that if you’re dining on fruit at each meal and/or snack, then you’re removing opportunities to eat more fibrous vegetables that are naturally very low in sugar. Additionally, frequent fruit intake elevates blood sugar levels (sugar is sugar is sugar) and thus insulin levels are often elevated, too. Only so much glucose and fructose can be stored in the liver and muscles so therefore the rest is converted to triglycerides or stored as body fat.
Consider fruit as a healthy dessert that contains awesome nutrients. The vitamins, minerals, fiber, and antioxidants are all fantastic but just keep total sugar intake in mind when taking inventory of your total nutrient intake for the day. Two final notes: dried fruit and fruit stored in syrup is loaded with added sugar and should be avoided; and if you opt for high-sugar fruits, keep your serving size smaller than what you would serve for low-sugar fruits.