This is a very important topic, although mostly beyond the scope of this book, which focuses on the dietary priorities around the treatment phase of having cancer. However, one thing to emphasize here is that there is a difference between eating to prevent cancer and eating when you are in treatment for cancer.
Research has shown that a healthy weight, being active and plant-based dietary approaches may help prevent around 30 per cent of cancers, but once you actually have the disease it is still not clear to what extent diet can influence its progress or risk of recurrence. This is a growing area of research and more scientific studies are needed before we can fully understand the role of diet and lifestyle in the prevention of cancer after recovery from treatments for the disease.
Hence at this time the recommendations for eating well and being active are that, after treatment for cancer, people should follow the primary cancer prevention guidelines.
1Be as lean as possible without becoming underweight.
2Be physically active for at least 30 minutes every day.
3Avoid sugary drinks and limit consumption of energy-dense foods (particularly processed foods high in added sugar, or low in fibre, or high in fat).
4Eat more of a variety of vegetables, fruits, wholegrains and pulses such as beans.
5Limit consumption of red meats (such as beef, pork and lamb) and avoid processed meats.
6If consumed at all, limit alcoholic drinks to two a day for men and one a day for women.
7Limit consumption of salty foods and food processed with salt (sodium).
8Don’t use supplements to protect against cancer.
9It is best for mothers to breastfeed exclusively for up to six months and then add other liquids and foods.
10After treatment, cancer survivors should follow the general recommendations for cancer prevention.
And always remember – do not smoke or chew tobacco.
Please be aware that these guidelines will not be suitable for every one after treatment. If you are underweight, have experienced significant weight loss, have had surgery affecting your digestive system, have swallowing difficulties or have bowel problems or any other difficulties eating a normal diet, you should ask your doctor, dietitian or specialist nurse if these recommendations are suitable for you.
The guidelines are also general guidelines for cancer prevention. However, the different types of cancer can all be influenced by different dietary factors. You can find out more about factors which either have no impact or can increase or decrease the risk of some of the dietary-related cancers from the WCRF/AICR’s Expert Report, Food, Nutrition, Physical Activity, and the Prevention of Cancer: a global perspective. Amendments and updates are constantly being made as we continue to gather more research around diet, exercise and cancer prevention.
Although some of the terms may not be familiar to you, it gives an idea of the range and depth of the scientific research that went into producing the Report. Visit <www.dietandcancerreport.org> to find out more about it.
I also invite you to download or order a booklet I wrote with WCRF, Eating Well and Being Active Following Cancer Treatment. It provides more detail on the Report and guidelines for healthy lifestyle approaches to help reduce cancer risks after treatment. It is available for free from <http://www.wcrf-uk.org/PDFs/EatingWellBeingActive.pdf> or the WCRF (see Useful addresses).
The following topic is one I like to discuss with the people attending the nutrition presentation in our cancer survivor programme.
You will often hear that this food or that is the latest superfood, or that one food is better or has more super-antioxidant powers than another. Turmeric is claimed to be a better spice than cumin. The gogi berry is apparently better than the pomegranate, and of course dark chocolate and red wine have been given the green light. In actual fact I am quite sick of hearing about the latest and greatest superfood – and really there is no such thing, as variety is what it is all about.
However, across the cancer research world there has been continuing interest in a particular group of food chemicals called the phytochemicals. Scientists have been working to unravel the mechanisms and potential therapeutic benefits of many of these potent phytochemicals, which occur naturally in plant foods, to determine whether they have a role in cancer prevention and other health problems.
This is not an easy task as there are over 100,000 different phytochemicals in plant foods including fruits, vegetables, nuts, seeds, pulses and wholegrain cereal foods. There can also be quite wide variations between concentrations according to the season, the plant variety, the ripeness of the food and whether the phytochemicals exert their effects individually or synergistically – in other words, do combinations work together to exert an overall greater benefit?
One group of French researchers have tried to narrow the field somewhat and have started looking at one group of these phytochemicals, called polyphenols. Polyphenols have been an area of interest around cancer research for some time: there have been over 6,000 studies on polyphenols and cancer.
What is helpful to us practically minded folk is that this French research has measured and listed for us the top 100 polyphenol-rich foods. Using a method which is more advanced than those used previously, they have put together the Phenol Explorer database <http://www.phenol-explorer.eu/>.
Polyphenols are a large class of compounds found in plants. They help defend against attack by insects and give plants their colour. From our point of view, they are valuable because they are some of the most potent antioxidants available. They have a particular chemical compound structure characterized by the presence of at least one ‘phenol’ unit and so are also referred to as phenolics. ‘Poly’ means ‘many’ and ‘polyphenols’ simply indicates large numbers of these compounds grouped together. While no one can be expected to remember them all – there are over 4,000 different polyphenol compounds – it is good to know that they are on your side and act as powerful antioxidants that can neutralize free radicals, reduce inflammation and slow tumour growth.
A good way of knowing whether they might be in your food is that these polyphenols are the chemicals that give the bite or astringency to foods. You’ll notice it in tea that’s brewed too strong (the compound once called tannin) and in the ‘greenish’ flavour of extra-virgin olive oil or the back palate of red wine. Anything that makes your mouth pucker a little generally contains polyphenols.
Although there are thousands of polyphenols, a few examples include: resveratrol, found in red wine; capsaicin, found in chilli and paprika; thymol, found in thyme; cinnamic acid, found in cinnamon; and rosmarinic acid, found in rosemary, thyme, oregano, sage and peppermint (remember my push for herbs and spices?).
The Phenol Explorer database has summarized polyphenols in two top 100 lists – the first gives the richest 100 foods by concentration, while the second has foods ranked by their content per serving. The lists show you the best foods and beverages that provide more than 1 mg of total polyphenols per serving.
They range from 15,000 mg per 100 g for cloves down to a tiny 10 mg per 100ml for rosé wine. Many spices and dried herbs appear on the ‘per 100 g’ list but not on the ‘per serving’ list as their serving size is so small (usually less than a gram or a pinch), although this richness is another good reason to remember to try to use them to add more flavour to your foods.
Tea, on the other hand is ranked only 52 (black) and 54 (green) on the ‘per 100 g’ list but makes it to 16 and 17 in the ‘per serving’ list, as we drink sizeable quantities (200 ml/7 oz in a cup); for many people tea will be their main source of polyphenols.
So while this information is helpful and interesting, it needs to be emphasized that it is not about paying inflated prices for the latest superfoods, but about jazzing up meals with some top-up tastes, more colour and spice, and more variety from the thousands of these potent health-supporting nutrients.
Here are a few more ideas for how you can do this. Remember, it means aiming for lots of colours of fruits, vegetables, nuts, seeds and wholegrain cereals, and it is very easy to open a can of pulses to add to a salad or the family stew.
Try to add a little more of the following:
•Spices: cloves, star anise, capers, curry powder, ginger, cumin, cinnamon, turmeric.
•Herbs (including dried): peppermint, oregano, sage, rosemary, thyme, basil, lemon verbena, parsley, marjoram, coriander.
•Seeds: flaxseeds, celery seeds.
•Nuts: chestnuts, hazelnuts, pecans, almonds, walnuts, pine nuts.
•Bread: rye, wholegrain wheat flour, soy and linseed breads (Vogel).
•Olives: black olives, green olives.
•Vegetables: globe artichokes, spinach, red chicory, green chicory, red onions, spinach, broccoli, curly endive, peppers, potatoes, pulses, carrots.
•Dark berries: black chokeberry, elderberry, blueberry, plum, cherry, blackcurrant, blackberry, strawberry, raspberry, prune, black grapes, redcurrants.
•Fruit other than berries: apples and apple juice, nectarines, pomegranates and pomegranate juice, peaches, grapefruit juice, blood oranges and blood orange juice, lemon juice, lime juice, apricots, quinces, grapes, prunes, pears.
•Oils: extra-virgin olive oil, rapeseed (canola) oil.
•Beverages and extras: filter coffee, green tea, black tea, red wine (in moderation), cocoa beverages with milk, dark chocolate, soya tofu, soya milk and yoghurt.
Remember, this is a fast-moving science and not all foods have been measured yet. The researchers also mention the following as worth keeping in mind:
•Lentils, dried oregano, dried summer savoury, dried bay leaves, dried camomile, dried coriander, fenugreek, dried winter savoury, pistachio, hyssop, red Swiss chard leaves, dried dill, raisins, black pepper, fresh peppermint, figs, fresh lemon balm, fenugreek seed, tarragon.
Remember, if you are having trouble eating or swallowing, to adjust the texture of the food using a hand-held blender.
•Orange, cut into quarters
•Bowl of whole oats with an added seed and berry mix, a topping of fresh berries, a sprinkle of cinnamon and skimmed or soya milk
•Cup of tea.
•Vegetable soup (try beetroot, carrot, minestrone, lentil and chard, etc.)
•Salmon, avocado and baby spinach salad with baby tomatoes, with a vinaigrette dressing made with flaxseed oil, garlic, chopped parsley, coriander and lemon juice
•Soy and linseed thick toast or wholegrain pitta bread.
•Grilled lean lamb cutlets or chicken with basil pesto sauce, broccoli, asparagus, carrots
•Small serving of brown rice or baby or new potatoes
•Low-fat berry yoghurt with extra fresh blueberries (drizzle melted dark chocolate for a treat).
•Apple, oat and flaxseed muffin
•Handful of nuts mixed with dried raisins and organic apricots
•Home-made berry smoothie (make with fresh or frozen berries)
•Fresh fruit
•Crackers
•Slice of malt loaf or fruit bread.
Table 10.1 lists some simple ideas for bringing more phytonutrients into your day.
Table 10.1 Some simple ideas for bringing more phytonutrients into your day
| Swap the regulars … | … for some of these alternatives or additions |
| Iceberg lettuce | Darker lettuce such as mignonette, baby spinach, rocket, red cabbage, parsley (try tabouli), chervil leaves |
| Potato | Sweet potato, pumpkin, chick peas, lentils, aubergines, parsnip, baby potatoes, corn, beetroot (mix in spices like nutmeg) |
| Green beans | Spinach, bok choy, peas, chard, cabbage |
| Pears and apples | Oranges, mandarins, grapefruit, tangelo, berries, kiwi fruit, mango, pawpaw, pomegranate, pineapple (add cloves, cinnamon, star anise, mint) |
| Potato crisps | Mixed nuts, salted cashews, almonds, walnuts |
| White fish fillets | Atlantic salmon, fresh tuna, canned salmon, canned sardines, swordfish |
| Puffed or flaked cereal | Oat-based cereal (muesli, rolled oats, oat and fruit flakes) or sprinkle a tablespoon of ground flax or linseed or rice bran over your favourite cereal |
| Ice cream | Thick low-fat Greek yoghurt topped with cinnamon (or other mixed spices) and honey, low-fat soya or custard |
| Salt | Sage, coriander, lemon juice, sherry vinegar, ginger, cumin, black pepper, basil, chilli |
The more you experiment with cooking, the better and more confident you will become. This gives you more ability not only to enjoy your old favourites, but also to make small changes that will improve taste and flavour as well as the contribution they can make towards your health.
If you have not been a regular cook, learning may seem difficult at first. However, it is exactly like trying to learn a new sport or language – it feels uncomfortable or impossible to start with, but the more you practise the better you become.
Part of learning to cook is to become familiar with a wide range of fresh and interesting ingredients. Try your local farmers’ market, fishmonger or speciality food outlets. Talk to the suppliers and try to learn more about food and its ingredients. It can also be helpful to have good equipment (non-stick frying pan, electric griller, wok, microwave, food processor, hand-held blender, oven rack, baking paper) and a good set of knives.
It is important not to be afraid to make changes to the way you prepare many of the traditional dishes you may have cooked.
•Reduce the butter, oil or cream that you add to recipes. Usually the same results can be achieved by using a fraction of the original quantities, particularly in older-style recipes. Other substitutes can include low-fat yoghurt, ricotta cheese or evaporated skimmed milk.
•Instead of frying in oil or butter, cook basic ingredients such as onion or garlic in water. This is just a lower-fat approach to cooking. For example, if you are making a soup it is fine to cook the onions and garlic in water instead of oil.
•Drain meat if cooking in a frying pan. For example, if you are cooking a bolognese sauce you should strain the meat to allow the fat to drip away after browning.
•Switch to low-salt varieties, and instead of adding salt to your cooking learn to appreciate the tastes of fresh herbs, lemon and garlic.
•Readjust the portions of meat to vegetables in your recipes. Allow a small palm-sized portion of meat per person and bulk up with more vegetables, legumes such as lentils, chickpeas, barley, rice or pasta. Small canned varieties of beans are a quick and easy way to add legumes to your cooking.
•Trim all the fat off the meat you do eat. Take the skin off the chicken and trim all visible fat off meat; roast on a rack.
•Filo pastry can be used to make a quiche or pie instead of the more traditional types of pastry.
•Try oil-free bastes or marinades.
•Popcorn can be cooked in the microwave and eaten unbuttered.
•If you are baking, try to cut the butter or margarine by one-third. Add some extra fruit such as a mix of dried or mashed fresh fruit, e.g. mango or banana can be folded into a cake mixture.
•Try not to add sugar to recipes. Sweeten with stewed fresh fruit or try vanilla essence.
•Heavy sauces are out these days. Instead of a gravy or cream-based sauce, try a lighter jus or just splash on some good quality balsamic vinegar.