In a meeting today, my companion asked me about my views on fruit and fruit juice. In short, my reply was that I think fruit is over-rated, and that fruit juice should generally be avoided. Many of the reasons for my ambivalence about fruit (and why much fruit is anything but some sort of nutritional nirvana) is, for me, well articulated in this blog post by nutritionist Zoe Harcombe. Personally, I do eat some fruit, but I don’t go out of my way to eat it either.
My issue with fruit juice specifically concerns its very sugary nature. Only last month, our attention was drawn to this fact by a comment piece written in the journal Lancet Diabetes and Endocrinology [1]. The authors, from the Institute of Cardiovascular and Medical Sciences in Glasgow, UK, first alert us to the potential for sugary soft drinks (such as cola) to contribute to weight gain (something that they put down to the tendency for these drinks to supply calories that are not compensated for by reduced intake of other foodstuffs). And then they deliver these cool, hard facts:
…fruit juice has a similar energy density and sugar content to [sugar sweetened beverages]: 250 ml of apple juice typically contains 110 kcal and 26 g of sugar; 250ml of cola typically contains 105 kcal and 26·5 g of sugar.
The authors point out that, generally, people tend to underestimate the amount of sugar in fruit juices and smoothies, while generally overestimating the sugar in soft drink. Here’s a graph which represents the results of a study they conducted on this.
These results mirror my own experience: almost everyone I talk to about fruit juice is shocked at how much sugar they contain.
The authors point out that fruit juice and soft drinks are not the same, and that fruit juices may contain vitamins and minerals that could be of value for ‘individuals consuming micronutrient-poor diets’. However, as they also point out, this may not be enough to offset the ‘adverse metabolic consequences of excessive fruit juice consumption.’
The authors go on to say:
…in the UK only the first 150 ml of fruit juice consumed can count towards the five-a-day target—the inclusion of any fruit juice at all as a fruit-equivalent in this recommendation is probably counterproductive because it fuels the perception that drinking fruit juice is good for health, and thus need not be subject to the limits that many individuals impose on themselves for consumption of less healthy foods. Accordingly, we suggest that better labelling of fruit juice containers is needed, to include explicit recommendations on maximum recommended daily intake. A further, more radical suggestion would be to re-examine whether any fruit intake in the form of juices should be permissible within guidelines for daily fruit and vegetable intake. This change would be in line with calls in the USA that recommend elimination of all fruit juice consumption by children.
Overall, I agree very much with the sentiments expressed in this article. And it seems some manufacturers are feeling the heat. Back in 2009, PepsiCo launched Trop50 – a range of fruit juices diluted with water to reduce the sugar content by half (and sweetened with stevia). Over the coming years, I expect to see a growing number of ‘low sugar’ fruit juices and smoothies on the shelves.
References:
1. Gill JMR, et al. Fruit juice: just another sugar drink? Lancet Diabetes and Endocrinology published online 10 February 2014.
When the manufacturers start climbing onto the “reduced sugar fruit juice” bandwagon, it will be interesting to see how much they charge for the added water.
I don’t drink fruit juice very often but when I do it gets diluted – 1 third juice to 2 thirds water – which does make a refreshing drink.
What’s the betting that the manufacturers don’t reduce the price.
I agree with John & Christine. I tend to emphasise the veg part of the 5-a-day because most overweight people happily eat enough fruit (and often juices/smoothies) but rarely enough veg.
When I buy fruit juice, which is rare, I always dilute it with a third to a half of water. I was also please to see Trop50, but dismayed to see added sweetener. Not because I have anything against sweeteners, but because it’s totally unnecessary in my view. Fruit juice is already very sweet. It annoys me that manufacturers seem to want to continue and strengthen our preference for very sweet flavours. Trop50 on promotional price was still more expensive than normal fruit juice. Because it’s sweetened, I expect when I do try it, I will want to add water to that too, just to make it more palatable. I do the same with no added sugar cranberry & Pomegranate juices, which I probably consume most frequently of all the juices.
If the nutritional benefits of fruit juices are marginal, then when does a sugar based beverage with added vitamins & minerals become a better choice nutritionally? Most energy drinks contain large doses of B vitamins. Iron Bru could perhaps be argues to contain a useful amount of iron. The soft drink picture is complicated by phosphoric acid but my feeling is that sugar loaded milkshakes are already more nutritious than fruit juices, but on the downside they are more energy dense and not so easily diluted, although I often do dilute them with milk/nut milk just to make them less sweet to suit my palate.
I regard fruit juice as sugared water. It’s just another con by food/drink manufacturers to sell unhealthy products under the guise of ‘healthy’. I couldn’t stop laughing when “Vitamin Water” came out.
When you say “fruit juice” and smoothies are you referring to those that you can purchase that are manufactured, etc. Or also freshly squeezed fruit juice at home ? My wife always says there’s a massive difference between the two, however, I’m not sure. Can you please clarify.
Dr John,
Can you confirm whether blending fruit etc raises the glycemic index (in the way that mashed potato has a higher one than boiled). My first trawl of the literature is ambiguous.
I agree entirely that undiluted fruit juice is not needed if you wish to lose weight.
The glycemic index (GI) or glycemic load (GL) can be a reflection of the macronutrient balance with in a food, and the amount of digestible matter that’s present. Essentially GI and GL measure and indicate the speed with which glucose (mainly from carbohydrates) enters the blood.
Sugars, starches, soluble fibre, and insoluble fibre are really variations on the same thing. They are, in essence, polymer molecules built around bringing molecules of glucose together to form the polymer. The term used to classify them as group is polysaccharides. Essentially the simpler (smaller) the polysaccharide is the sweeter it will taste, the more easily it will be digested, and the more it can spike your blood glucose (BG). In nature the simpler polysaccharides are more prevalent in summer, which helps raise BG, helps spike insulin, helps induce lipogeneisis (creating fats to store) and helps ensure fats are pressed into the fat cells found around the tum, hips, and thighs. In the wild, the prevalence of of simpler polysaccharides helps species prepare for winter by increasing body-fat stores.
If you cook, blend, or mash, puree, juice, or whatever, the effect is to release the simpler polysaccharides from a complex structure that has them contained by fibrous structure that is a mix of indigestible polysaccharides, some of which may be soluble fibre, and some of which may be insoluble.
High GI or GL is really brought about by the presence of the simpler polysaccharides and the absence of the features that put the brakes on digestion. Fibre and containment by fibrous material (natural structure) are features that put brakes on digestion and result in slower passage of glucose over the gastrointestinal (Gi) divide.
Most pre-consumptive process (cook, blend, or mash, puree, juice, or whatever) is an assault upon structure and containment, so yes, you should expect it to raise GI or GL, and spike your BG.
High GI or GL and spikey BG are interpreted by the body and its hormones to be cues that replicate conditions of summer. If you normally expend 2500 calories your hormones may start encouraging you to eat 2700 calories per day, and that extra 200 finds its way to your waistline.
The presence of fats in the food we eat and in the Gi tract is also a bit like fibre, in that it is a physical barrier that slows digestion. Satiety signals may well be fat centric. Supplying sufficient fat encourages fat burning and lowers pressure on BG and insulin. With insulin levels lower your body can break away from lipogenesis, and leptin can have its say.
Leptin is a hormone whose purpose signals: ‘You have fat stores to spare, you need not eat 2500 calories per day because some of the energy your body needs can come from those fat-stores round your middle’ Leptin will suppress appetite, and you’ll feel fine eating, say 2000 calories, without feeling hunger. Leptin is the reason, amongst others, a hibernating bear does not wake for a midwinter feast when all about is in deep freeze.
Lipogenesis is the summer balance of metabolism, lipolysis and ketosis (fat release and fat burning) is the winter mode.
Modern life for a human mostly provides cues to the endocrine system (hormones) that signal summer, even in winter.
Our metabolism is a modal energy system, and in this it is not unlike the power station at Port Dinorwic. Ours is governed by hormones, ‘Electric Mountain’ has a rather large switch driving some impressive relays.
http://www.electricmountain.co.uk/
Christopher Palmer – thank you so much for your clear explanation of GI and GL and also the difference between Summer and Winter metabolism. In order to make changes to our eating habits we need a proper understanding of the effects – the ‘whys’ and ‘hows’ and these you have provided. I feel I have a much better comprehension having read your contribution.
Regards
Janet
Thanks Janet,
What’s been written on GI and GL is quite helpful, but the tables and the details amount to no more than a tool really. What matters most is the aggregate glycemic load commuted to the body through the overall balance of the diet. High aggregate GL sends a clear message that it is ‘summer’ and time to prepare for ‘winter’.
My thinking has been influenced by Wiley and Formby and their book, ‘Lights Out’.
Metabolism is modal, it has to be. The calorie count does not influence the modes quite so much as hormones do.
Thank you Christopher. Sorry I didn’t reply earlier. You’ve clarified a lot and convinced me not to “smoothie” or puree unnecessarily
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Also, they rot your teeth. My sister was losing her tooth enamel at an alarming rate. The dentist asked her what she drank at the pub and she proudly replied, Britvic Orange. He suggested she take up beer drinking.
I agree with John on this one. Our modern fruits are a far cry from traditional fruits that humans ate. They have been bred to increase their sugar content. Excess fructose from any form more than 20-25 grams per day tends to be converted to triglycerides.
Occasional fruit is OK, but can the juice.
I’ll show this post to my mother–I’ve tried to tell her that juice is liquid sugar.
I’ve been almost entirely off fruit for so long that the smell of it is unpleasant.
If fruit juices contain just as much sugar as soft drinks then does that mean I should let my kids have Coke when out for a special occasion meal rather than encouraging them to have fruit juice? The other day my son asked for a pint of orange juice and I had to explain to him that a glass of OJ was okay but a pint wouldn’t be good for him.
I think a pint of orange juice would probably give him the ‘back door trots.’
Aurora: Dissolve a vitamin C tablet into a glass of Coke and it’ll offer all the benefits of orange juice to him, albeit with less sugar!
My daughter does not drink soft-drinks, nor fruit juices, nor squash. She drinks water, and full-cream Guernsey milk. For a treat, she has “sparkly water”. I cannot for the life of me see why this should be a matter of debate with a child.
For what my opinion is worth, I believe there is a million miles between eating a fresh apple or orange, than drinking fruit juice from a box or can. Eat whole fresh foods, dump processed junk and be healthy. The less man is involved, the healthier the foods.
People are waking up to the lies and hype from peddlers of junk and big pharma.
Kind regards Eddie
Everybody jumped on the fruit smoothie bandwagon as I did myself, thinking it was great for my health.
WRONG! The amount of sugar I was consuming was ridiculous, I could not believe it.
Being informed that something is good for our health does not necessarily mean that it is.