Nutritionist Sarah Di Lorenzo: Sugar free not as sweet as it sounds

All you need to do is take a walk down any supermarket confectionery aisle right now and you’ll find an ever-growing selection of sugar-free chocolates promising all the indulgence with none of the guilt.

As a clinical nutritionist, patients ask me about these products constantly and my answer is always the same — It depends entirely on what’s in it and how much you’re eating.

So what is actually in sugar-free chocolate? The marketing is so clever, the “sugar-free” label tells you what’s been removed, but not what’s been put in its place.

Most sugar-free chocolates are sweetened with one or more of the following: erythritol, stevia, monk fruit, maltitol, xylitol, sorbitol, artificial (synthetic) sweeteners or inulin — each with a meaningfully different impact on your body.

Understanding these differences is essential before eating these products.

When it comes to artificial sweeteners, many older and cheaper brands are made with artificial sweeteners rather than natural alternatives. Look for numbers like 955, 951, 950, 954 and 952 on the wrapper.

I always encourage people to avoid any products containing artificial sweeteners because there is research linking consistent consumption to gut microbiome disruption, possible accelerated cognitive decline and paradoxically higher risk of weight gain.

Stevia is a natural, plant-derived sweetener with a glycemic index of zero.

Research has found that sugar-free dark chocolate sweetened with stevia, erythritol and inulin produced a 65 per cent lower blood glucose response compared to conventional dark chocolate in people with diabetes.

That is actually a real difference for anyone managing blood sugar.

Maltitol, however, is a different story. Despite being widely used in cheaper sugar-free chocolates, maltitol has a glycemic index of around 35 which is significantly higher than other sugar alcohols so it can raise blood glucose levels, particularly in people with insulin resistance or who have type 2 diabetes.

Many people don’t realise their “sugar-free” chocolate is possibly still spiking their blood sugar.

Research shows a few things, on the positive side, sugar-free dark chocolate does appear to offer a lower blood glucose impact for most people, and high-quality dark chocolate regardless of being sugar-free or not still contains flavonoid and polyphenol content, which research consistently associates with cardiovascular protection, reduced inflammation and improved insulin sensitivity.

But there are several concerning findings that have emerged in recent years that people really should be aware of.

Research has found that sorbitol, one of the most common sugar alcohols used in sugary products, lollies, and confectionery, can be converted into fructose in the liver so this triggers a similar metabolic effect to regular sugar. The risk appears to be particularly high for people with compromised gut microbiomes, where protective bacteria are insufficient to neutralise sorbitol before it reaches the liver.

The World Health Organisation released a guideline in 2023 recommending against the use of non-sugar sweeteners for weight control.

This was based on systematic review evidence showing no long-term benefit in reducing body fat and therefore a potential increased risk of type 2 diabetes, cardiovascular disease and mortality with sustained use.

So is it really a good alternative? In the right context and of course how it is formulated.

For those of you who are really interested in consuming these products, the strongest safety profiles are the sugar-free chocolate that is sweetened with stevia or monk fruit. These have the least impact on blood glucose and gut health.

I would suggest avoiding products sweetened primarily with maltitol or sorbitol, particularly if you have diabetes, insulin resistance, fatty liver or a sensitive gut.

The best choice is to opt for is 70 per cent or above dark chocolate. The higher the cocoa content, the more flavonoids and the less sweetener required making sugar-free dark chocolate a genuinely better option than milk chocolate equivalents.

Always remember chocolate is a treat, not a daily staple.

The evidence does not support using sugar-free chocolate as a weight loss tool or a healthy food.

It is to be treated as a better option for indulgence and especially for people managing blood sugar. That is where its value genuinely lies.

The best chocolate is a small amount of very good quality dark chocolate, eaten slowly and with full enjoyment.