Saturday 21 February 2015

Can chocolate be good for you?

A new chocolate bar claims to 'help keep you happy and healthy every day' - can chocolate really be as good for you as this product claims?

Although we've a separate entry on chocolate, this claim seemed so dramatic that it was worth its own entry. The product in question is ohso and it's even packed in handy sets of seven, so you can eat it every day.

The chocolate's website, excruciatingly titled 'ohsolovesyourtummy.com', is a little short on facts. There is no nutritional information in the 'Nutritional Guide', for instance - I finally found them tucked away under a secondary heading, but what it didn't say was whether the list was for the 'added sugar' or 'no added sugar' variety. So far, the company has failed to respond to a request for more information. (And the site could do with a proof read, as it includes "Ingredient's" and "refferred to".)

So what are ohso's health claims?
  • It's free from gluten and nuts and has 'no added dairy'. That's good if these cause you problems, though not difficult to find these days. For the vast majority of us, no health benefit.
  • Has 63 kcal in the 'no added sugar' bar and 72 kcal in the others. Certainly not a scary amount of calories. So is this really low calorie chocolate? In fact it actually says 'We add no dairy, so each bar of ohso is 72 calories.' But it's not particularly the dairy that piles on the calories in chocolate. This is a small, 13.5g bar. The same amount of Cadbury's Dairy Milk, which I think it's fair to say no one, not even Cadbury, would consider healthy (and certainly does contain dairy) has, wait for it, 72 kcal in 13.5g. Exactly the same amount.
  • It contains 'friendly bacteria', which survive passage through the gut 'three times better' than in a yoghurt drink. Sounds good. But just because bacteria survive the passage through the gut doesn't mean they stick around and do anything. And as the Probiotics section of Science for Life shows (see page 80), there are no proven benefits from consuming 'friendly bacteria' other than in some very specific medical conditions. 
  • It's cholesterol free. So what? As you'll see in the Cholesterol section of the book (see page 28), it has been known for some time that eating cholesterol has no significant impact on our cholesterol levels.
Not a lot of health value there, then. I couldn't see it on the website, but many of the reviews of the product also contain that old chestnut that dark chocolate is 'packed with antioxidants'. How many times do we have to say this? We don't need to consume extra antioxidants - it doesn't add to our natural antioxidant level and with some supplements it has been shown to increase the risk of death.

What's particularly worrying is the way that the chocolate is packaged in 7s and is labelled as containing 'your optimal daily amount of "friendly bacteria"'. This seems to be encouraging people to eat chocolate every day and that can't be a good thing. The other thing to bear in mind is that you will paying £3.99 for under 100g of chocolate. As a comparison I took a look at a quality brand of chocolate (Green & Black's) at Waitrose, so you couldn't accuse me of skimping on price - £2.19 for 100g of their Maya Gold, around half as much.

As we say in our chocolate section, consumed in moderation chocolate is fine - and no one can doubt that it tastes good. But to suggest that chocolate can help keep you healthy stretches a point to breaking.

Friday 20 February 2015

Brewer's yeast

Some health stores recommend brewer's yeast as a natural way of reducing cholesterol - but does it work, and is it safe?

Brewer's yeast, which is essentially a powdered fungus used in beer production, is one of the many wonder products you can find in a health food store. It is sold both as a way of getting B vitamins and chromium, and is sometimes claimed to reduce cholesterol. This claim is based on a number of studies - but the evidence is weak, with some studies showing no effect at all, and several centres of expertise suggest there is no basis for the claim.

What is certainly true is that where it has been suggested that brewer's yeast has a cholesterol reducing benefit, the product is being taken in doses of around 500mg a day (1-2 tablespoons in powdered form). One concern this raises is that this would result in receiving around 1,000% of the RNI of niacin ((the amount that is enough, or more than enough for 97% of the population), and there is good evidence that high doses of niacin can have negative effects. There are simpler ways to reduce cholesterol.

The other claimed benefits of brewer's yeast tend to be from the trace mineral chromium (for which there are various claims with mixed evidence) and a source of B vitamins, but as we make clear in the Vitamins and minerals section (page 111) a normal adult on a balanced diet should not need supplementation. By all means enjoy the brewer's yeast containing spreads like marmite or vegemite if you are in the 'love' camp - but it seems unlikely that it will provide much benefit as a supplement.

Niacin

Niacin, or vitamin B3 is added to white bread and cereals, and present in high doses in some supplements. But do we need this fortification?

As mentioned in the Vitamins and minerals section (page 111), vitamin B3, or niacin, is an essential micronutrient that supports the nervous system and is required for good skin. Deficiencies can result in weakness, loss of appetite, dermatitis, diarrhoea and, at the extreme, dementia. It is found in wholegrain products, peanuts, sesame seeds, fish and most meat.

You may have noticed that it is added to many breakfast cereals, and it is also added by law to white flour (and hence white bread) in the UK, as in the 1950s the government reacted to the new enthusiasm for white bread, which lacks some of the nutrients of the wholegrain equivalent. To be honest, the level in flour and bread isn't enough to make a huge difference - and these days few of us in developed countries lack niacin.

However, there is a concern about over-consumption of niacin in supplements. A young child, for instance, being given a multivitamin on top of a normal diet can end up with around 600% of their RNI (the amount that is enough, or more than enough for 97% of the population). And an adult taking a high dose of, say, brewer's yeast, could be on 1,000% of their RNI from that alone.

The reason this is a worry is that B3 is one of the vitamins that can cause problems in excess. At high levels it can cause skin flushes, rashes and at the extreme stomach bleeds and an increased risk of diabetes. Serious problems over and above the flushes are only likely to be caused by consumption well over 1,000% of RNI, but even so, this is a good example where unnecessary supplements can actually have a negative effect. And we particularly need to be careful with young children.

Vitamins aren't sweets and care needs to be taken with dosing, bearing in mind that most of us get a lot of vitamins already in our diet.

Sunday 8 February 2015

High fructose corn syrup

High fructose corn syrup is used as an alternative to sugar to sweeten some drinks, particularly in the US. It possesses no greater health risk than any other sugar - but do cut down on sugar!

This is one that is more of concern in the US than the UK, where it is unusual for high fructose corn syrup (or HFCS) to be used. The reason it tends to be used in the US is that it is cheaper than conventional sugar, apart from anything else because fructose, one of the two sugars in HFCS (the other is glucose), is sweeter than sucrose (the fructose/glucose combo in conventional sugar). This means that technically it is slightly healthier than sucrose, as you can use less HFCS than cane or beet sugar to get the same sweetness.

There is nothing magic about any of these sugars, and HFCS has less fructose concentration than, say, an apple or pear. And, to be absolutely certain, there has been plenty of good research done on HFCS which shows that there are no negative effects whatsoever, apart from the usual problems of sugar.

So that's it. It's yet another scare because HCFS sounds less 'natural' than cane or beet sugar. In the end it's the same stuff, but because fructose is sweeter than sucrose, you need less of it to get the same level of sweetness, so if you have a choice, you should go for the HCFS. Like all sugars, it's something we should consume in moderation. Like all sugars, almost all of us should consume less. But the dire warnings doing the rounds on social media making it a dietary bogeyman have no basis whatsoever.

LINKS

  • Sugar - page 102



Saturday 7 February 2015

Copper bracelets for health

It's easy to find shops selling copper bracelets and other copper-based things to wear that it is claimed will help reduce chronic pain and swelling, reduce the impact of arthritis and more. But does it work?

Copper is a relatively common element that we need to consume in trace quantities for a number of functions of the body, but we get plenty of copper in our diet and an excess can result in liver damage and brain deterioration, so it's not something to take as a supplement without medical advice. But how about wearing it?

The immediate scientific response is to wonder how wearing a copper bracelet, say, could have any impact on pains in other parts of the body. One claim, for instance, is that the body can draw metal out of the bracelet to help with cartilage replacement. There is no mechanism by which this could happen - and even if copper was absorbed, it would do more harm than good. This seems little more than an appeal to magic.

A study was carried out in the UK in 2013 which reported that wearing copper bracelets had no impact on these problems, and that any perceived benefit from wearing copper was simply a placebo effect.

On a separate claim, it is just possible that copper compounds, appropriately applied, could have some antibacterial benefits - but it isn't enough to wear a piece of metallic copper, and there is no evidence as yet of a wearable product containing copper or copper compounds have such a benefit.

So by all means wear a copper bracelet if you think it looks nice - but don't expect it to make you healthier.

Herbal medicine

Herbs have been used in all cultures as medicines and some have real medical benefits. but care has to be taken with herbal cures as they are poorly regulated.

In historical times, herbs played a major part in our medical treatment, though as early as the 17th century, when herbalist Nicholas Culpeper published his Complete Herbal, there was a debate between the proponents of herbal and chemical medicine. With a modern understanding of the active ingredients in herbs we can see that the distinction is artificial. Herbs are an effective source of chemicals that have an active effect on the human body, though often this effect is improved if the chemical agent is refined and modified.

So, for instance, willow bark, containing a chemical called salicylic acid, has been used to help reduce pains and fevers for at least 4,000 years. Unfortunately salicylic acid causes sharp stomach pains and can cause internal bleeding – so that relief came with a price. At the end of the 19th century, the German pharmaceutical company Bayer produced a painkiller called aspirin, which modified the active ingredient to the much less aggressive acetylsalicylic acid. The active ingredient of medical herbs has been repeatedly isolated and improved. Quinine for malaria, atropine and digitalis for the heart, for instance, all originated with herbal cures, but are much better and safer in their pure chemical form.

Herbal medicine has a strong presence in China, and there are herbal medicine stores on many of our high streets. Unfortunately, current herbal medicine still uses theories with no basis (such as employing a herb with the same shape as an organ of the body to treat that organ) and has rarely advanced. There are also well-documented dangers in taking herbal medicines at the same time as other medications. It is always worth checking with your doctor first.

The popular herbal treatment St John’s Wort, for instance, which has proved effective in helping with mild depression, has as many possible side effects as any prescription drug, from gastrointestinal pain to dizziness. It can cause serious problems with anti-HIV, anti-cancer drugs and contraceptive pills; plus it generally reduces the effectiveness of the transport mechanism carrying drugs into the bloodstream. Because of this it has been banned in France. You can’t assume that because a treatment is herbal it is safe in all circumstances.

Another significant problem with herbal treatments is that a herb rarely contains only one active ingredient – and it is almost impossible to give a well-controlled dose, as the amount of the chemical in a herb will vary from plant to plant. Where a prescription medicine will have isolated the useful chemical, in a herb you could be exposing yourself to a whole range of potentially unpleasant substances to get the beneficial one. But more worrying still is the reality that there is very little regulation of the quality of herbal medicines.

A major US study in 2013 analysed 44 processed herbal prod- ucts and 50 medicinal herbs from a range of suppliers. The results were shocking. Less than half of the products actually contained the labelled main ingredient. Nearly 60 per cent contained herbal species that weren’t listed on the ingredients. A third also contained fillers and contaminants that weren’t on the label. In three of the companies tested, none of the products contained what they said they did. In other studies, herbal medicines have been found to be contaminated with dangerous heavy metals and other extremely poisonous substances.

*UPDATE* In February 2015 the New York State attorney general's office accused four major US retailers of selling herbal supplements that were fraudulent and in some cases were contaminated with unlisted ingredients. These weren't backstreet herbalists, but Walmart, Walgreens, Target an GNC. Approximately four out of five products didn't contain any of the herbs on their labels. Many contained little more than rice and houseplants.

The products with non of the herb in included Gingko Biloba, St. John's Wort, Ginseng, Echinacea and Valerian Root. Typical fillers were rice, asparagus, wheat or grass and garlic, though oddly many of the samples actually claiming to be garlic had none in. This really emphasises how much you are at risk of getting anything but what you expect when buying herbal remedies.

So, while there are certainly benefits to some herbal remedies, the lack of a proper regulation and of a testing regime paralleling that used on conventional medication means that there will always be significant risks attached.