Fruit is one of those “slippery slope” cases within the Primal way of eating. More than that, for weight loss in general there are tons of different opinions on fruit. I want to address both. I want to take a look at the Primal perspective on fruit but also the physiological perspective – how does fruit impact fat loss? Should you eat fruit for optimal results? Are there ways to enjoy fruit and fat loss at the same time?
In the Paleolithic Era, fruit was not available year round. Our ancestors certainly enjoyed fruit when it was in season but it wasn’t available year round. During the warmer seasons when fruit was available and other food was more abundant, they would eat more with the intention of storing fat for times when food wasn’t quite so available. Fruit (and the sugar within it, known as fructose) is uniquely qualified for this job of storing fat. Let’s look a little closer at fructose and why we need to be very careful about how and when we consume it.
Fructose is the type of sugar found in fruit. It is the sweetest of all naturally occurring carbohydrates – sweeter than glucose! Because of its intense sweetness, the food industry has adopted it as an additive to enhance sweetness “naturally” via the development of high fructose corn syrup (HFCS). Now, fructose is hardly limited to fruit. Fructose (and HFCS) can be found in the majority of processed food products as a sweetener and to help extend shelf life.
Initially, fructose was hailed as a beneficial sweetener with positive health implications. This is totally untrue, but there’s a reason the food industry came to this conclusion. Whereas glucose can be used by any cell in the body for energy, fructose must be metabolized by the liver. When you eat foods containing glucose, they are broken down and the glucose goes to your blood stream, raising your blood sugar. Fructose skips that part. It doesn’t end up in the blood stream and so it doesn’t raise your blood sugar in the same way – it goes straight to the liver as the liver is the only place fructose can be metabolized. Sounds like a great thing – fructose won’t raise your blood sugar the way glucose does – but it’s not quite so simple.
Fructose is THE MOST lipogenic carbohydrate. In plain English: when compared to allllll other carbohydrates, fructose is the most easily and readily converted to fat. Bad news! With the fructose load in the Standard American Diet (coming mostly from processed foods) the liver gets easily overloaded and converts all that fructose very quickly and efficiently to fat.
It gets worse. Fructose encourages muscle and fat cells to become insulin resistant. Remember that insulin dictates fat storage/fat release. When your muscle and fat cells are insulin resistant, that accelerates fat storage and makes fat burning much more difficult.
Finally, fructose does not trigger satiety signals the way that other sweeteners do. This is why you can eat a pint of blueberries or an entire watermelon and never feel full. This is part of the reason that processed foods feel so addictive. It worked out really well for our Paleolithic ancestors – they could gorge on fruits and berries during the summer and store fat as energy for the winter. We, however, don’t experience periods of famine and fructose is abundant year round. The result: accelerated fat storage and slowed fat release.
The best thing you can do to prevent excess fat storage from fructose is to avoid processed foods. From there, however, be mindful of your fruit intake. For maximum fat loss, consider fruit a carbohydrate and enjoy it after a workout or with your evening meal.
For detailed information on carbohydrate strategies for fat loss including more on fruit, wheat, oats, gluten plus strategies for improving your carbohydrate tolerance, check out the comprehensive carbs & fat loss ecourse! Follow the link below and use the coupon code Primal10 to get lifetime access for only $69 (including troubleshooting help from me on demand!)