How do you eat as healthily as possible? (Photo: Pixabay)
In the first article we showed that a high VO2 max significantly reduces the risk of premature death from cardiovascular diseases and also from other diseases including even cancer. We therefore introduced the concept of fitness age and a calculator to calculate it.
In the second article we presented an additional analysis of life expectancy. After all, your life expectancy is also influenced by other factors, such as smoking, diet, blood pressure, cholesterol, heredity, lifestyle and psychological factors (feelings of happiness, stress). These factors can be expressed in the concept of biological age. You can then determine your broad life expectancy, which is equal to the standard life expectancy plus the difference between your age and your biological age.
We concluded this article with the following 10 rules for a healthy lifestyle. If you live according to these rules, the chance to reach a high age is maximized!
Lifestyle rules: the key to a long life
- Do not smoke
- Sleep soundly
- Train regularly and intensively
- Laugh to the fullest and enjoy your life
- Enjoy your relationship and your friends
- Manage your stress level
- Eat plenty of fruits and vegetables
- Avoid too much alcohol, sugar, salt, fat (saturated) and processed foods
- Avoid high blood pressure
- Avoid risks and environmental pollution
In the third article we looked at the efficiency of training and calculated how much your life expectancy increases per hour you train. The conclusion was that the return on investment from training is very favourable: your ‘profit’ in life expectancy is far more than the ‘investment’ in training hours.
In the fourth article we dealt with the influence of personality and lifestyle using the book of the Canadian and 60-time world record holder Earl Fee “100 Years Young, the natural way“. In our article we have summarized some telling examples:
- Importance of optimism, positive thinking and feelings of happiness
- Importance of good habits
- Importance of ‘mental exercise
- Importance of ‘cleaning up
- Importance of spiritual thinking
How does nutrition affect your health and life expectancy?
Today we close the series with an article about the influence of nutrition. Is there a causal link between nutrition and disease or life expectancy? We have read a lot of literature on this subject, including the book of emeritus professor of nutrition Prof. Martijn Katan “Nutrition myths“. He concludes that we are swamped with reports of beneficial or harmful effects of food and drink. The so-called beneficial effects are often not based on hard science, nor are the supposed adverse effects. Katan argues that there are many myths about nutrition. These myths arise because researchers allow themselves to be tempted to thicken their findings. This leads to exaggerated press releases. The media are happy to publish them because food news is always popular. Nutritional myths meet many needs, including those of the food industry, which often funds research….
In his book Katan deals with seventy food myths. He ends with the message: News about nutrition can usually be ignored. The information in the media is usually new and exciting but almost always wrong and not based on hard science.
So what kind of hard science is there about the influence of food on our health and life expectancy?
In our opinion, the best source for this is the Health Council of the Netherlands’ advisory report “Guidelines for Good Nutrition 2015“. This is the official advice to the Dutch Cabinet and Parliament from an extensive committee in which virtually all Dutch experts in the field of nutrition were represented. It was not made in haste, because the Minister’s request for advice dates back to 1998….. In those intervening years the current state of the science was summarized. Among other things, this has resulted in 29 background documents on individual foodstuffs. The advice itself counts 93 pages and can be seen as a summary of the state of the science on the basis of strict quality requirements. In addition to the committee, the Dutch Nutrition Centre and the Dutch National Institute for Public Health and the Environment also contributed to the advice.
Research Methodology Guidelines Good Nutrition 2015
The committee has investigated the relationship between food and the risk of chronic diseases. It primarily looked at the Dutch top 10 diseases, namely coronary heart disease, stroke, heart failure, diabetes, chronic obstructive pulmonary disease (COPD), breast cancer, colon cancer, lung cancer, dementia and depression. In addition, the committee looked at risk factors, for which a causal relationship with at least one chronic disease has been demonstrated. These are systolic blood pressure, LDL cholesterol and body weight.
In terms of types of research, the committee distinguishes between randomized and controlled intervention research (RCTs) and prospective cohort research.
In RCTs, participants are divided into groups on the basis of chance, with one group receiving treatment (food) and the other group serving as control. Well-executed research of this type provides the best clues to the causality of a relationship. From RCTs, the committee draws conclusions about the effects of intake on causal risk factors and chronic diseases in the various background documents and about the level of evidence for these conclusions.
In cohort research, the link between nutrition and chronic diseases is investigated without the researcher intervening in the existing situation. Cohort research provides less strong evidence for causality because bias can never be excluded. The question is whether sufficient corrections have been made for the influence of lifestyle variables (smoking, alcohol consumption, exercise, etc.).
Finally, the committee made use of publications from peer-reviewed journals in which data from several studies were published, the so-called meta-analyses. These give a greater statistical power of discernment and a more accurate estimation of a correlation.
The figure below from the advice gives an overview of the research methodology used.
In formulating guidelines, the committee has based itself on conclusions with great evidential value:
- The food affects a causal risk factor. These are results from
- The food is related to the risk of disease. These are results from a cohort study, we speak of a connection.
Summary Advice Guidelines Good Nutrition
The core of the advice is to eat according to a more plant-based and less animal-based diet. This is elaborated in guidelines for the food products fruit and vegetables, meat, fish, nuts, legumes, cereals, butter and oil, beverages, alcohol, cooking salt and food supplements. In the table below we have summarized the advice.
In this article we will point out the most important conclusions:
- Fruit and Vegetables
The committee concludes that it has been convincingly demonstrated that eating fruit and vegetables reduces the risk of coronary heart disease and stroke. Cohort research also shows that eating fruit and vegetables is associated with a lower risk of diabetes, colon cancer and lung cancer. The recommended amount is 200 grams of vegetables and 200 grams of fruit. On average, Dutch people eat too little vegetables (125 grams) and fruit (120 grams).
- Wholemeal bread and wholemeal products
The committee concludes that there is convincing evidence that the consumption of wholemeal products reduces the risk of coronary heart disease and stroke. Cohort research also shows that eating wholemeal products is associated with a lower risk of diabetes and colon cancer. The recommended amount is 90 grams per day; the average consumption in the Netherlands is approximately at this level.
The committee concludes that it has been convincingly demonstrated that the consumption of legumes lowers LDL cholesterol and thus the risk of coronary heart disease. Incidentally, half of the population in the Netherlands eat little or no legumes (soybeans, lentils, chickpeas or split peas).
- Unsalted nuts
The committee concludes that it has been convincingly demonstrated that consumption of unsalted nuts reduces the risk of coronary heart disease. The recommended amount is 15 grams per day, in the Netherlands half of the population does not eat unsalted nuts (walnuts, almonds, hazelnuts, cashew nuts, pistachios, macadam nuts, Brazil nuts and peanuts).
The committee concludes that it is plausible that the consumption of dairy products is associated with a lower risk of intestinal cancer and diabetes. The recommended amount is a few servings per day, including milk or yogurt. The average dairy consumption in the Netherlands is at this level.
- Oily fish
The committee concludes that it has been convincingly demonstrated that eating fish reduces the risk of coronary heart disease. In cohort research, eating fish is also associated with a lower risk of stroke. The recommended consumption is to eat fish once a week, preferably fatty fish (herring, salmon, mackerel). In the Netherlands, half of the population eats 2 to 3 servings of fish per month.
The committee concludes that there is convincing evidence that the consumption of tea reduces the risk of stroke. It is also plausible that the consumption of tea is associated with a lower risk of diabetes. The recommended quantity is 3 cups per day.
- Replace refined cereal products with whole grain products
The committee stresses the importance of replacing refined with unrefined grain products. Replacing sugars with starch leads to a reduction of LDL cholesterol. Starch is a healthier source of carbohydrates than sugars. The average consumption of refined cereal products (white bread, pasta, etc.) in the Netherlands is about 100 grams per day.
- Replace butter and roasting fats with liquid fats and vegetable oils
The committee concludes that it has been convincingly demonstrated that replacing butter and frying fats with liquid fats and platear oils reduces the risk of coronary heart disease.
- Replace unfiltered coffee with filtered coffee
The committee concludes that it has been convincingly demonstrated that unfiltered coffee increases LDL cholesterol and thus the risk of coronary heart disease. In cohort research, the use of filtered coffee is associated with a lower risk of heart disease, stroke and diabetes.
- Eat little red or processed meat
The committee concludes that it is plausible that there is a link between the consumption of red meat and processed meat and a higher risk of stroke, diabetes, intestinal cancer and lung cancer. The link is stronger with processed meat than with red meat.
The guideline is to limit the consumption of red meat and especially processed meat. On average, Dutch men eat about 105 grams of red meat per day and 55 grams of processed meat.
- Beverages containing sugar
The committee concludes that it has been convincingly demonstrated that the consumption of sugary drinks increases the risk of diabetes. Good alternatives are water, tea and coffee.
The committee concludes that it has been convincingly demonstrated that high alcohol consumption increases the risk of stroke. In addition, high alcohol consumption is associated with a higher risk of breast cancer, bowel cancer and lung cancer. However, it is plausible that moderate alcohol consumption is associated with a lower risk of cardiovascular disease, diabetes and dementia. Low wine consumption is associated with a lower overall mortality rate. The committee recommends not drinking alcohol or at least not more than 1 glass a day.
- Kitchen salt
The committee concludes that it has been convincingly demonstrated that a reduction in sodium intake lowers blood pressure and thus the risk of cardiovascular disease. The recommendation is to limit the intake to 6 grams of table salt per day. The average intake for Dutch men is currently 10 grams per day.
- Food supplements
The committee concludes that the use of dietary supplements is not necessary, except for people belonging to a specific group for whom supplementation advice applies. Examples are vitamin D advice for young children, pregnant women, the elderly and people with dark skin or body covering clothing. Pregnant women need extra folic acid and vegans need extra vitamin B12.
In addition to the recommendations for specific foods, the committee also looked at so-called ‘recommended diets’, such as the Mediterranean diet, the Scandinavian diet and the American Dietary Approaches to Stop Hypertension (DASH). These patterns score high on the use of vegetables, fruits, wholemeal products, nuts, legumes, vegetable oils, skimmed dairy, poultry and fish. What characterizes the patterns is that they contain less animal and more vegetable foods. This is even more true for vegetarian food. The committee concludes that it has been convincingly demonstrated that the recommended dietary patterns reduce the risk of coronary heart disease and stroke. Furthermore, these patterns are associated with a lower risk of diabetes, bowel cancer and mortality everywhere. It has also been convincingly demonstrated that vegetarian diets reduce the risk of coronary heart disease. In conclusion, the committee recommends eating according to a more plant-based and less animal-based diet.
So far our summary of the Good Nutrition Guidelines. Following the committee’s advice, the Dutch Nutrition Centre and the Dutch Consumers’ Association have translated this into practical brochures and books, including the Disk of Five. The readers of ProRun will probably have seen or read various things earlier. Nevertheless, we thought it would be a good idea to revisit the committee’s own report, which can be seen as the compilation of scientific knowledge about the influence of food on health.
Our book ‘The Secret of Running’ is for sale in our webshop. Also available in German as ‘Das Geheimnis des Laufens’, and in Italian as ‘Manuale completo della corsa’.