Sunday, February 02, 2014
The paleo diet: can it really be good for you?
Most reformed serial dieters can remember a defining moment that got them off the starvation treadmill. Mine came in 2008. I was meeting an old friend, the nutritionist Charlotte Watts, for brunch. She walked in and something – everything – had changed. Her skin was clear and glowing, her eyes were bright. Her body looked stronger and leaner.
“You look amazing,” I said.
“I’ve gone paleo,” she replied.
Over the three months since I’d last seen her Charlotte had been “eating the way our ancestors did”: she’d given up sugar, processed foods, grains and legumes, focusing instead on meat, fish, vegetables and fruit. As a health writer, I pooh-poohed the idea (all that meat? There’s a global food crisis! And what healthy diet says give up lentils?) and continued to jump on and off whichever new vegan diet, alkaline plan or juice fast I happened to be writing about.
But Charlotte’s energy stuck around, as did her new figure. Meanwhile, on my high-in-wholegrain-and-dairy and low-in-meat-and-fat diet, I was tired, moody, 10lb overweight and always craving pasta or chocolate.
Then, in 2011, Charlotte and I wrote a book together and in the interests of research I tried her approach. Six weeks in, I had lost 4lb and felt unbelievable. I was back at the gym after years of desperate tiredness, had lost my afternoon crisp cravings, was sleeping better and thinking more clearly.
Although the idea of eating “what we’re programmed to” has been around since the 1960s, it was only in 2001, when the high priest of paleo, Loren Cordain, published The Paleo Diet, that it began to grow in popularity in America. By 2013 it had became the most Googled diet on the internet. It’s now taking off in Britain, too, with Amazon listing nearly 20 new paleo diet books out this month alone.
Cordain’s thesis is simple. A professor in the department of health and exercise science at Colorado State University, he argues that certain foods entered our diets only about 10,000 years ago with the agricultural revolution, when we began cultivating grains in larger amounts, and that isn’t long enough for us to adapt to eating them.
Instead, he believes we should stick to what the cavemen ate – meat, vegetables, fruits, seeds and nuts – and avoid grains, along with anything that prehistoric man wouldn’t have recognised, such as dairy, pulses, sugar and, of course, processed food. The book spawned an almost cult-like following, and his disciples – including the former runner Mark Sisson and a research biochemist called Robb Wolf – have built a mini-industry of cookbooks, eating plans and DVDs.
As well as the upsurge in popularity, something else has happened paleo-wise: it’s now women who are waving the flag. Celebrities such as Jessica Biel and Miley Cyrus have come out as fans, while the bloggers Sarah Fragoso, of Everyday Paleo, and Diane Sanfilippo, of Balanced Bites, boast tens of thousands of followers on Twitter. Their approach is less strict, allowing for the occasional bowl of porridge, but they promise results that go beyond mere weight loss.
“I used to get a sinus infection every two months, I struggled with acne and had depressive tendencies,” Sanfilippo tells me via Skype from her home in New Jersey. “I started paleo in 2010 and saw immediate changes to my skin and my mood, and I haven’t had a sinus infection in three years.”
Sanfilippo, who is also a nutritionist, believes that women are suddenly embracing the lifestyle because “it gives them permission to eat fat without getting fat… Adding fat to meals means that they are often satisfied with less food and usually lose weight. For my female clients that’s a revelation.”
Devotees aren’t without their critics, however. An article on the American food website Grub Street observed how female followers “all fit a similar mould… sporty, healthy, attractive. That’s no coincidence, of course. They’re ambassadors for the brand, and they need to look the part.” One response in the comments section read, “Has the author of this article considered that maybe the paleo-women look the way they do because they eat a healthy diet?”
While we are all familiar with the stereotypes surrounding gender and food – that is, men supposedly favour meat, and women salads and cupcakes – what causes such preferences remains unclear. Is it conditioning or biology? It’s hard to say. Dr Lucy Cooke, a behavioural psychologist at University College London, found that boys showed a clear preference for fatty foods and meat while girls were more willing to eat fruit and vegetables. These differences became more pronounced in adolescence, indicating that social conditioning may have a part to play.
She also found that genes were a more important factor than gender in food choice. This certainly rings true for me: my grandmother, like me, would far rather have gnawed on a chicken bone than picked at a cherry sponge, so perhaps I was destined to find the paleo diet appealing all along.
Whatever you call it – primal, caveman or paleo – no diet is quite so divisive. John Briffa, a doctor, nutritionist and ardent supporter of primal eating, points to evidence from fossilised remains that show “our ancestors pre-agriculture were robust physically, tall, strong and lean”. Remarkably, a study of the hunter-gatherer people of the Trobriand Islands in Papua New Guinea found an absence of heart disease or diabetes, while a three-week trial of the paleo diet at Karolinska Institute in Sweden recorded an average weight loss of 2.3kg and a drop in blood pressure among participants.
But large-scale studies are non-existent – the Swedish one involved 14 people – and, in light of their absence, many nutritionists remain vehemently opposed to the paleo diet. In its 2013 ranking of 28 diets, which took into account safety, nutrition, weight loss and the effects on diabetes and heart disease, the influential US News & World Report placed paleo joint last (with the Dukan Diet). Its panel of experts “took issue with the diet on every measure”.
“The paleo diet trend is a dangerous fad,” says Lucy Jones, a spokeswoman for the British Dietetic Association (BDA). “There isn’t any proof that it improves health, and its demand that you exclude food groups essential to health such as dairy, grains and legumes could leave people seriously deficient in essential vitamins and calcium, not to mention constipated from the lack of dietary fibre.” (One thing dietitians do agree on is sugar, which is increasingly blamed for poor health, with the Action on Sugar campaign comparing it to smoking and alcohol in harmfulness.)
Besides, asks Jones, what was the life expectancy for hunter-gatherers? About 20? Indeed, only a minority of our paleo ancestors would have made it to their forties, and many children would have died before they reached the age of 15.
But John Briffa remains adamant. “What with warfare, high risk of infection and climate, life expectancy was short,” he says. “But our ancestors were healthier than we are today during their short lives.”
Others question the reasoning behind the diet. According to Marlene Zuk, a professor of ecology, evolution and behaviour at the University of Minnesota and the author of the book Paleofantasy, the very idea that we haven’t evolved for 10,000 years is itself suspect. “A strong body of evidence points to many changes in the genome since humans spread across the globe and developed agriculture,” she says.
Jones also points to studies that link red meat with an increased risk of bowel cancer, though Briffa disputes the reliability of them. “Most of these studies look at populations of people and infer cause and effect from one characteristic of their diets, such as meat-eating,” he says. “How do you know their cancer was caused by red-meat eating, rather than some other attribute common among red-meat eaters, such as being sedentary or eating processed foods?”
Jones’s concerns do make sense to me, but, after three years, paleo eating is the one diet that has made me forget about dieting. It’s given me, at 44, huge reserves of energy, and I no longer feel hungry. According to the nutritionist Petronella Ravenshear, whose clients are mostly tired, stressed and slightly overweight women like I was, this is not uncommon among those on a paleo diet.
“The first thing you usually see is weight loss,” she says. “Because it contains enough protein and fat from meat, nuts and seeds, a paleo diet also balances out insulin levels. This generally means they are less hungry between meals because the protein sustains them longer than carbohydrate. They’re not getting blood-sugar crashes a couple of hours after eating. Their calorie intake consequently goes down naturally.”
So what’s so wrong with grains and legumes, which have been prescribed as part of a healthy diet for decades? Briffa and other paleo nutritionists claim that the gluten in wheat, barley and rye can trigger an immune response, with all sorts of ill effects, from headaches to fatigue and musculoskeletal pains, in those with a sensitivity to it. Online, you’ll find a barrage of claims about paleo curing everything from depression to autism.
Most links remain anecdotal, although Prof David Perlmutter, a neurologist and the author of Grain Brain, has used MRI scans to show how gluten causes changes in the brains of those sensitive to it. He claims that 40 per cent of people cannot process gluten properly, and says that it could trigger changes associated with depression, ADHD, headaches, dementia and autism.
Even the BDA concedes there may be a link. “Some patients with neurological conditions such as autism do respond to dietary restrictions,” says Lucy Jones. “There is a condition called ‘leaky gut syndrome’, in which the proteins from grains such as wheat and legumes may leak into the bloodstream of someone with a sensitivity and trigger an immune response. But as dietitians we simply don’t have enough evidence to say that such an approach will work across the board for all autistic children or those with other neurological conditions.”
Sarah Bowles-Flannery, a naturopath and nutritionist, says that paleo diets have benefited clients with Crohn’s disease, colitis and the autoimmune disease Hashimoto’s thyroiditis. Briffa and Sanfilippo, meanwhile, credit them with helping clients with rheumatoid arthritis and even multiple sclerosis.
Like Sanfilippo, I, too, no longer suffer regular sinus infections. Gone are my mood swings and the overwhelming need to sleep all day on Sundays. I now wake at 5am to exercise and manage to put in 12 hours at work most days. And yet I find a truly paleo diet a struggle to sustain – buying lunch at M & S usually means only chicken breast or salmon flakes and a bag of salad. At restaurants friends have called me a pain in the a—, because I’m always asking whether things contain dairy and opting out of potatoes or rice. It becomes boring and repetitive, and so I have made my own concessions to the hardcore rules laid out in Cordain’s covenant – as do most people who eat primally long-term.
I succumb to the odd chickpea curry, eat porridge made with water and salt every few days, the occasional chip off my partner’s plate and anything I am served at dinner parties. Otherwise I couldn’t keep paleo going.
“I would always recommend people be flexible,” says Sarah Bowles-Flannery. “If you love porridge and want to have a lentil curry a few times a week, that’s fine. Most of the benefits come from cutting out sugar and processed foods and not eating grains all the time.”
Now I eat red meat only once a fortnight, usually lamb from a farm run by a friend who breeds a small herd each season. I’ll rarely have more than 100g to 150g of meat or fish (a portion the size of an iPhone) and avoid processed or charred meats altogether, as evidence suggests it’s these that increase the risk of bowel cancer. “That’s the big mistake everyone makes on paleo diets,” says Bowles-Flannery. “They go mad on meat but their diet should be three-quarters vegetables and fruit, the rest lean protein and healthy fats such as nuts, avocados and seeds.”
Still, it takes getting used to. “At first, paleo eating feels restrictive and boring,” says Petronella Ravenshear. “But within weeks the improvements in energy and general wellbeing make my clients – especially the women – want to stick with it. It’s like it’s given them permission to eat instinctively, freeing them from dieting and calorie-counting. The words I most often hear after someone has gone paleo are, ‘I feel liberated.’”
The paleo diet, deconstructed
Meat Red meat, game and poultry are encouraged, as long as they form no more than 25 per cent of your diet. Fish is eaten freely.
Nuts and seeds Although loaded with fats, they’re high in protein.
Fruit and vegetables Fruit is not prohibited, but the lower in sugar, the better (eg apples and pears). Generally any quantity of vegetables can be eaten, except for potatoes, which are high on the glycaemic index (GI) and cause spikes in insulin levels. Some paleos do eat lower-GI sweet potatoes.
Sugar Causes blood-sugar spikes and energy crashes.
Grains and legumes Believed to contain sticky, sugar-binding proteins that wreak havoc on the gut. The gluten in grains is blamed for causing inflammation of the gut and even the brain.
Dairy said to cause constipation and other gut issues. Paleos believe only about 40 per cent of people continue to produce lactase, the enzyme needed to digest lactose, in adulthood.
Dry January is over, but did it actually HARM your health? Expert claims having regular tipple is better for you than abstinence
Many of us will have woken up feeling especially smug this morning – not to mention slightly richer – after successfully negotiating the whole of January without a drink. After the excesses of the festive period, what better way to cleanse the system than a month without booze?
However, the increasingly popular practice of detoxing the body during ‘Dry January’ may do more harm than good, according to one expert.
He claims that having a regular tipple throughout the post-New Year period would have been more likely to improve health than giving up alcohol completely.
Professor Charles Bamforth, of the University of California, Davis, said: ‘Many people don’t realise that drinking in moderation has significant health benefits and that moderate drinkers have a longer life expectancy than non–drinkers. ‘Regular moderate intake of alcohol is good for the heart and blood circulation.’
The author of Beer, Health and Nutrition said drinking to excess can cause serious problems, but added: ‘The key is a little and often.
'You are seriously mistaken if you think that having a month without drinking will protect you from the effects of excessive drinking for the rest of the year. ‘The best advice is to drink moderately throughout the year.’
Prof Bamforth said beer, and in particular real ale, contains many nutrients that are important for a healthy body. He said: ‘The great thing about beer is that it is low in alcohol and brewed from natural raw materials, so it’s a good source of important nutrients such as antioxidants, B vitamins and dietary silicon that promotes strong bones. Indeed, beer used to be known as liquid bread.’
The Campaign for Real Ale welcomed his comments, suggesting older people could see particular benefits.
Chairman Colin Valentine said: ‘The health benefits of moderate drinking may explain why you meet so many people enjoying a healthy retirement who still like going for a pint of real ale in their local.
‘The evidence also shows that sociability has significant benefits to health and well-being. You are far better off sharing a beer with friends in a pub than sitting at home drinking by yourself.’
Posted by jonjayray at 12:21 AM