Reviewed by: Fiona Bannister, Accredited Practising Dietitian
In his book, Gillespie talks about how he believes low fructose diets are more effective for weight loss than low fat diets. He claims that after years of low fat foods being heavily promoted, people were still becoming fatter. Furthermore, in the last 150 years, we have gone from eating minimal amounts of added sugars to an average of 1kg per week.
Sweet Poison’s RULES on Fructose:
1. DON’T DRINK SUGAR
Avoid all drinks that contain fructose, such as soft drinks and fruit juices. Diet soft drinks are ok, but Gillespie advises against them due to risk of cancer. Alcoholic drinks (except dessert wines and sparkling wines) are fine if the mixer is fructose free.
2. DON’T SNACK ON SUGAR
Avoid all sugary processed snacks such as biscuits and cakes. Snack on nuts instead as they contain fat which will trigger appetite regulating hormones to tell us when we are full.
3. PARTY FOOD IS FOR PARTIES
Avoid all foods that you would expect to find at a child’s birthday party (sweets, icecream, jelly, cake).
4. BE CAREFUL AT BREAKFAST
Most cereals contain dried fruit and sugar. Suggests cereals containing <10g ‘sugars’ per 100g. Low fructose breakfast options include bacon (0% fructose), eggs (0%), white bread(2%) and Rice Bubbles (5%).
5. THERE IS NO SUCH THING AS GOOD SUGAR
Be wary of labels claiming ‘ No added sugar’, as will usually contain high amounts of naturally occurring fructose. Also, be careful with ‘Low Fat’ products as they usually contain more fructose than lower fat varieties.
Gillespie recommends you eat about 10 g of fructose a day – an amount provided by a couple of pieces of fruit. ”However, the average Australian male is actually consuming 60 to 75 grams of fructose every day,” he says.
To support his theory that fructose promotes weight gain, Gillespie discusses his findings from researching this subject. His main points are:
- When we eat fructose our bodies do not release appetite-regulating hormones (such as insulin and leptin) which signal to our bodies that we are full. Other fuels we consume, such as fat, protein and other sugars, stimulate the release of these hormones.
- Energy production from fructose is not regulated by our bodies. Hence, eating lots of fructose ‘overloads’ our energy production system (or ATP system) which results in fructose being converted straight into fat.
- Eating whole fruit is ok as fibre makes it difficult to consume too much of this fructose containing food.
- Fructose foods are addictive. When we eat fructose, opiate receptors in our brain are stimulated in much the same way they would be if we were to use a drug such as cocaine.
Flaws of the Low Fructose Diet:
- It is not surprising that followers lose a lot of weight on the low fructose diet, considering so many foods contain fructose and hence are cut from the diet which is likely to result in an energy deficit.
- Following this diet is quite similar to Atkins as it is low in carbs and can be high fat, which may result in a diet that promotes CVD
- There is a lack of evidence on the relationship between fructose and obesity.
- Most studies cited in Sweet Poison are conducted on animals.
- Some sources cite that Australia’s consumption of sugar has actually decreased by about 23% over the past 30 years.
- While there is evidence that pathways in the brain that are activated by addictive drugs are activated by foods, there is a lack of research on how different foods affect those pathways (EG whether sugar is more addictive than fat).
Tags: book review, David Gillespie, fructose, sugar, sweets







Hi Fiona,
I would be very interested in your assessment of this study due to be published in The Journal of Clincal Endocrinolgy & Metabolism. Seems to add weight to the hypothesis that fructose (but not glucose) is a contributing factor in increasing the blood factors associated with increased heart disease risk.
http://www.medscape.com/viewarticle/747245