Eat fish – it’s full of omega-3’s… wait don’t – it contains PCB’s and mercury. Drink milk – you need the calcium… don’t drink milk, it causes prostate cancer. Eat soy… actually don’t. Drink coffee… stop drinking coffee…
Nutrition is a deeply confusing topic. Joe Schwarcz, PhD is hoping to change that.
An Apple a Day: The Myths, Misconceptions and Truths About the Foods We Eat, is a comprehensive and refreshingly evenhanded look at what we know, what we think we know, what we don’t know and how we can apply what we do know to our nutritional choices. Instead of giving dietary plans, Schwarcz teaches us how to think about nutrition and does so in a thoughtful, humorous and engaging manner.
The book is broken down into 4 parts:
- Naturally occurring substances in our food supply
- Manipulating our food Supply
- Contaminants in our food supply
- Tough to swallow (a look at fads and shaky science)
Here are some nuggets from the first part of the book;
‘It is folly to think that one can introduce something as complicated as food into something as complex as the human body and make easy predictions about the outcome.” – Joe Schwarcz
- “Toxic chemical” is a meaningless term unless placed in its proper context. Apples contain acetone, isopropanol and cyanide. It’s the dose that counts.
- Polyphenol content in the diet is inversely associated with death from heart disease. Major sources in the diet are apples, tea and onions. The real key to antioxidant intake is variety
- An Italian study showed that higher pizza consumption was associated with lower risk of heart attacks. The tomato sauce appeared to be the link. After studying tomato products and lycopene, it appears that it is processed tomatoes that are responsible for the health effects – not the lycopene itself.
- Cranberries help ward off urinary tract infections however it is not due to the acidity or anti-bacterial effect. It is the prevention of bacteria sticking to the lining of the urinary tract – which is thought to be because of the trimeric procyanidins. Duh!
- Blueberries have powerful antioxidant effects – possibly due to the anthocyanins and pterostilbenes found in the little blue wonders. A study showed that young rats could balance on a narrow beam for 13 seconds. When the rats reached old age, it dropped to 5 seconds. The old rats fed blueberry extract, however were able to stay on an average of 11 seconds.
- Compounds found in orange peels (polymethoxylated flavones – PMF’s) have been shown to exhibit a powerful cholesterol-lowering effect (the study had only 10 subjects, however). Commercial concoctions are being formulated and tested. These PMF’s also exhibit qualities similar to tamoxifen – an anti-cancer drug. More research needed.
- Acai berries – turned into expensive commercial juices, claim to have more antioxidants than any other fruit. What matters though, is total antioxidant intake and this appears to be best served by consuming a variety of fruits and vegetables. Antioxidant capacity is tested in a lab dish – which may or may not carry over to human benefit.
- There is a strong inverse relationship between fish consumption and depression – with some countries exhibiting 60 times the amount of depression as others. Ditto with cognitive impairment, ADD, dyslexia and hyperactivity
- Studies on fish consumption and heart health have been very promising and yet surprisingly mixed. 2-3 servings of fatty, cold water fish (salmon, sardines, herring and mackerel) is a good idea. Enough to induce benefits and not enough to worry about mercury and PCB’s
- Flaxseeds contain lignans, which have been shown to lower breast cancer risk. Flax also binds to bile acids in the gut – forcing them to make more. Diabetics have experienced a 30% drop in blood glucose with 50g of flaxseeds.
- Olive oil contains oleocanthol, an anti-inflammatory substance with pharmacological activity similar to that of ibuprofen. Phenols found in extra virgin olive oil reduce the damage to DNA in colorectal cells.
- In addition to fiber, whole grains contain vitamins, mineral and antioxidants. They also provide lignans (anti-cancer effects) and rutin – which can reduce the risk of blood clots.
- Beta-glucan found in oats prevents cholesterol from being oxidized, lowers blood pressure and helps control blood sugar levels
- In the Nurses Health Study, women who consumed beans and lentils twice per week were about 25% less likely to develop breast cancer than those who ate them less than once a month. This may be due to the inositol pentakisphosphate found in beans, lentils, peas, wheat bran and nuts that has an effect similar to the drug cisplatin – a drug commonly used to treat ovarian cancer
- Look for gas-free beans in the grocery stores soon. Adding lactobacillus species before cooking can reduce gas-producing carbohydrates by 90% without altering nutritional value.
- Breast cancer rates in the former East Germany were much lower than those in West Germany. The possible difference? Cabbage consumption was much higher in East Germany.
- Higher intakes of foods rich in lutein and zeaxanthin such as spinach, corn and collard greens are associated with a substantially lowered risk of macular degeneration
- Turmeric, the yellow spice used to add flavour to dishes has a powerful anti-inflammatory effect. More specifically, curcumin – a component of turmeric inhibits the action of cyclooxygenase-2 enzyme (COX-2) which catalyzes inflammation
- Curcumin may also be effective in preventing colon cancer
- The Health Professionals Follow-up study (45,000 men) found that total coffee intake was not associated with heart disease or stroke even when consumption exceeded 4 cups per day. Coffee consumption appears to decrease the risk of Parkinson’s disease and type II diabetes
- Resveratrol found in red wine has been shown to simulate the positive effects associated with reducing calories by 30%. French paradox? Mais Non! They eat less than Americans do. Comparisons of restaurants have shown that American restaurants portions are 25-72% larger than that of comparable French restaurants. American candy bars are 41% larger and hot dogs are 63% larger. The average French person takes longer to eat meals. The average American spends an hour eating per day while the average French spends 100 minutes.
- Celiac disease (gluten allergy) is strongly associated with non-Hodgkin’s lymphoma and is much more common than we may think.
- Cinnamon has been shown to reduce blood sugar levels by as much as 30% – with only a quarter tablespoon a day. In this study, it also lowered LDL cholesterol and triglycerides
- Homocysteine appears to signal the approach of heart disease, but doesn’t cause it. Levels can be lowered with folic acid, vitamin B-6 and vitamin B-12 – but this didn’t effect heart disease when put through clinical trials. Lowering homocysteine does however appear to lower risk of colon cancer and Alzheimer’s disease but appears not to have an effect on cognitive performance in the elderly. Uncooked spinach is a great source of folate
- While high doses of vitamin E don’t appear to reduce the risk of heart disease or cancer but it appears to ward off Parkinson’s disease and cold sores.
- Vitamin D offers significant protection from breast cancer. Doses need to be at about 1000 IU’s for protection – supplementing is usually necessary to achieve this. Subjects from a multitude of studies who took vitamin D were less likely to die of ANY cause than those who did not (by 7%).
Other heated topics discussed in the book:
- Milk and whether or not it does the body good
- Why the fear of MSG and artificial sweeteners and is largely irrational
- The science and technology behind artificial colours and flavours and whether or not we need to worry about them
- An in depth look at food preservation techniques and which ones we need to be concerned about
- A look at food fortification and its impact on our health
- A look at possible food contaminants and substances in our foods (dioxins, PCB’s, antibiotics, hormones)
- The truth behind claims of super juices, supplements, Kosher foods and detox diets
For me it is nice to know there are books available that teach people how to think about nutrition and food amongst the countless that prescribe diets and preach single-minded messages. An Apple a Day is a very scintilating read for those interested in digging a little deeper into the complex interplay between food and health. It is rich with science, straightforwardness and impartiality and manages to boil down complex topics into easy-to-understand take home messages.
If you’re interested in the bottom-line, user-friendly guidelines and black-and-white suggestions, you may find the book a little too drawn out. On the other hand, if you are looking to expand your basic undertanding of nutrition and navigate through food contoversies, I think this book is of good value.