Can vitamin supplements do more harm than good? Should we be spending more time in the sun? What are phytonutrients and why are they important for our health? Is physical activity more important than dieting? Are meat, dairy products and saturated fats good for our health? Can what we eat affect our mental health?
These are some of the questions Glenn Matten and Aidan Goggins explore in The Health Delusion. To find the answers they have sifted through more than 600 scientific articles in peer review journals. Here are some of their conclusions:
Antioxidant vitamin supplements aren’t usually needed. In fact some of them can increase mortality. For instance one meta analysis looked at 22 Randomised control trials (RCTs) of antioxidant supplements (vitamins A, C, E, beta carotene and selenium). It found no protective effect against cancer. Instead the studies suggested a 50% increased risk of bladder cancer.
The idea that we need large supplements of antioxidants to fight free radicals is now discredited. Our bodies need some free radicals, for instance to help our immune systems fight off infection. Too many antioxidants (like too many free radicals) are bad for us. We need to keep a natural balance.
Selenium and Vitamin D are the two exceptions, where supplements can sometimes help. If you live in the US you won’t normally need a selenium supplement, as wheat grown there is from selenium rich soil. However, if you live in Europe, where the soil is selenium deficient, the authors recommend a small supplement (50 – 60 mcg per day for women and 100 mcg per day for men). More than this is likely to increase your health risk. Like antioxidants, you only need enough to keep the right balance in your body.
Because the main source of Vitamin D is from the sun if you live in the UK or other countries far from the equator you won’t get enough sun (and the right kind of sun) during the colder months of the year. So, in the UK, a Vitamin D supplement (1,100 – 1,200IU per day) is recommended from the end of October to the end of March .
Spend time in the sun. This is the main source of vitamin D – which is good for our bones; and also associated with a lower risk of cancer, heart disease, diabetes, depression and Alzheimer’s. We know that too much unprotected exposure to the sun increases the risk of skin cancer but we need some time in the sun, without sunscreen, to gain the benefits of Vitamin D. Aim for minutes rather than hours here.
Beige is bad. Avoid or limit white bread, white pasta, pastries, biscuits, cakes, battered and breadcrumbed convenience foods. These fill you up with ‘empty calories’ rather than the nutritional elements your body needs.
Plant foods (like fruit and vegetables) contain a cocktail of nutrients that are good for our health – like vitamins, fibre, potassium, lycopene, lutein, flavonoids, glucosinolates (and an appropriate amount of antioxidants) . Flavanoids, for instance, lower blood pressure, inhibit inflammation, inhibit cancer cell growth and even protect the brain against neurodegeneration. Compared with supplements they provide a mix of nutrients, in the right quantities, in a form our bodies have been used to consuming and making use of for thousands of years.
Diets can work in the short term but regular exercise is a more effective way of managing your weight long term. That’s because the body adapts to diets by increasing appetite and also by a process called ‘adaptive thermogenesis’- designed to preserve body fat and ‘protect’ the body from further weight loss. This makes it increasingly difficult to sustain weight loss.
If we look at the US, the amount of calories consumed hasn’t changed much in 30 years. What has changed is the amount of physical exercise – with fewer active occupations, more labour saving devices, more car use and more time sat in front of a TV or computer. According to the authors, compared with 50 years ago, this cumulative reduction in the amount of exercise is ‘the equivalent of running a marathon a week’ ie exercise rather than dieting is the key to losing weight. Exercise also has a range of other health benefits, from healthier bones to reduced mortality. In fact The Health Delusion reports, ‘the repeated finding that individuals who are fit and overweight have lower rates of diseases and mortality than unfit ‘healthy weight’ individuals.’
Dairy isn’t the enemy – what we need is enough vitamin D to balance dairy’s calcium content. In countries which drink a lot of milk there’s a higher incidence of some cancers, like prostate cancer. However, it seems the problem arises through a combination of too much calcium and not enough vitamin D. The countries which drink most milk tend to be in higher latitudes, with less sunshine and thus less natural vitamin D. Given an adequate level of vitamin D, calcium in dairy products can actually help protect against breast cancer and colon cancer.
White meat is OK – be careful how much red meat you eat and how it is prepared and cooked. Red meat is a good source of protein, well absorbed iron, zinc and vitamin B12, so it is OK to include some in your diet – but in moderation. Eating three 8 oz steaks (or the equivalent in chops, roasts, burgers or mince) could increase your risk of bowel cancer by 29%. Frying, grilling or barbecuing increases a cancer causing chemical (HCA) – so stewing and boiling are safer, with slow cooked casseroles a good option. Marinating meat before cooking (especially if the marinade includes herbs and spices) also reduces the risk. As does eating or drinking flavonoids alongside the red meat (like onions, green tea or after dinner dark chocolate). Avoid processed red meats as they increase the risk of bowel cancer, through their use of nitrate preservatives.
A vegetarian diet has some advantages but also some important nutritional deficiencies. Vegetarians tend to experience good health, with less chronic disease and greater life expectancy. This is partly due to the health benefits of eating a wide range of plant foods (like fruit, vegetables, wholegrain cereals, beans and nuts). However, plants alone can’t give us all the nutrients we need for our hearts, brains, immune system, hormones and bones. Fish and low fat dairy products are a good complementary source of nutrients.
Saturated Fat isn’t actually bad for us, High GI Carbs is the main risk, and Omega 3 Fats are good for us. A 2010 meta analysis of 21 studies covering 347,747 people, ‘found no evidence to conclude that dietary saturated fat was associated with an increased risk of coronary heart disease, stroke or cardiovascular disease.’ The risk is from high Glycemic Index carbohydrates (the ‘beige is bad’ foods mentioned earlier – like processed, white bread, pasta and rice). Omega 3 oils (found in oily fish) are good for our hearts.
What we choose to eat can influence whether we get depression, whether we get dementia and even anti social behaviour. Countries with a high consumption of fish and seafood (like Japan) have lower levels of depression and lower levels of homicide – and a study in Chicago found that people who ate fish once or more a week had a 60% lower risk of Alzheimer’s compared with those who rarely or never ate fish. This is part of the evidence presented for the value of emega-3 rich fish oil. However, there are some caveats. One element in fish oil (DHA) seems to block the effectiveness of another element (EPA) in reducing depression (although DHA seems effective in helping prevent dementia). And once you have dementia, fish oil doesn’t seem able to reverse this.
The Health Delusion also looks at the different types of medical research and which carry most weight (along similar lines to our analysis here on Age Watch) ; considers whether ‘you are what your mother ate’ (the ‘Foetal Origins’ hypothesis we also assess elsewhere on Age Watch); and suggests we focus on diet and lifestyle to remain healthy, with prescription drugs a last resort and even then combined with appropriate nutrients to either enhance their effect or reduce the risk of harmful side effects.
Because it covers so much ground there are sometimes tantalising disparities which aren’t picked up and explored further. For instance, having spent a chapter arguing against multi vitamin supplements the authors later report, with apparent approval, that multivitamins reduced antisocial behaviour in trials in young offenders institutions. A 2005 study is reported which found an association between prostate cancer and low fat milk, whereas other research suggests low fat milk has a protective effect against breast cancer and yet another study suggested yoghurt (rather than milk) was the culprit when it came to prostate cancer. From a reader’s perspective it would probably have been useful to have an overview section which looked at individual foods and weighed up the main pros and cons from the evidence available.
Sometimes too the research quoted is from the 1990’s, so not necessarily the most up to date – although, to be fair, most of the research cited is more recent.
Overall, though, The Health Delusion provides an impressively wide ranging and evidence based review of what we can do to optimise our health through nutrition and exercise – and a good understanding of the complexity of the human body and the importance of maintaining balance within it. It reinforces much of what we report here on Age Watch, as well as raising interesting questions about which are the true heroes and villains when it comes to antioxidants, the sun, dairy products, diets and saturated fats. It is written in a very readable style, is clearly laid out and has useful summaries at the end of each chapter.
The Health Delusion has even impressed health professionals. Writing in the GP magazine Pulse, Dr Pam Brown commented, ‘I was surprised by how much I learnt and just how rapidly the evidence-base is evolving, as it becomes understood that drugs alone are not enough for chronic disease management.’
The Health Delusion – How to achieve exceptional health in the 21st century Glenn Matten and Aidan Goggins (Hay House ISBN 978 – 1 84850 – 686 – 2)