Do we lose all the important vitamins and minerals during cooking? Is there any truth behind nutrient timing? How many eggs are we “allowed” per day? Does caffeine make us dehydrated? Despite the huge amount of information regarding healthy nutrition that is available nowadays, dietary facts and fiction is not easily distinguishable.
Can nutrient timing help you lose weight?
The concept of “chrono-nutrition” or nutrient timing is very popular as a weight loss technique based on the fact that there are small fluctuations during the day and night in the levels of various substances in our bodies, such as the hormones used in metabolic processes. The theory behind this concept is that there is an ideal time for digesting protein, carbohydrates and fat because of these changes. Macronutrients consumed outside the periods of optimal digestion will not be utilised but stored as fat, resulting in weight gain. For example, foods containing proteins, fats and slowly digested carbohydrates should be eaten at breakfast and mainly protein containing foods at lunch.
The truth is that whenever we eat proteins, fats or carbohydrates our body responds by increasing the production of all substances needed to digest and utilise them. Any weight loss experienced with this diet is probably due to the reduction of overall calorie intake and portion control.
Is all the goodness in vegetables lost during cooking?
This idea has some truth to it as water soluble vitamins like vitamin C and folic acid are susceptible to oxidation. As a result much of them is lost when foods containing these vitamins, such as green vegetables, are cooked in large volumes of water which is discarded. This loss can be minimised if vegetables are not cut up, put straight into boiling water and served immediately. An even better solution is steaming vegetables or cooking them with very little water in a microwave oven. Interestingly, other nutrients, such as fibre and other antioxidants remain in the vegetables and may become more available to the body through cooking. Additionally, we shouldn’t forget that proper cooking increases the microbiological safety of foods and usually enhances their flavour.
Does caffeine cause dehydration?
Caffeine has been reported to have a diuretic effect above 250 mg per day and it can therefore lead to increased water loss and possibly to body water deficit, although this effect may be less pronounced in regular caffeine consumers. However, research suggests that normally consumed amounts of caffeine in drinks such as tea, coffee and colas do not increase fluid loss because the water we get from these drinks can contribute to our total fluid when consumed in moderation. National authorities around Europe recommend a water intake of at least 1.2 litres (4-6 glasses) in adults. This is in addition to the water we get from food and our metabolism, to replace losses through urine, faeces, perspiration and the lungs.
Should we eat no more than three eggs per week?
High blood cholesterol levels are one of the main risk factors for coronary heart disease. This has led to the idea that egg yolks, which are rich in cholesterol, are bad for cardiovascular health. The truth is that about 75% of the body’s cholesterol is made in the body, and the dietary cholesterol generally has little effect on the blood levels. In addition, saturated fat has a much greater effect on blood cholesterol than dietary cholesterol, and eggs are low in saturated fat. Therefore, most health and heart advisory bodies in Europe no longer set a limit on the number of eggs consumed as long as they are consumed as part of an overall balanced diet.
Are sweeteners linked to cancer and other adverse health effects?
Low calorie sweeteners have been available for more than a century and they’re used in a broad variety of foods and drinks. Their popularity lays in the fact that they are the low calorie alternative to sugar and therefore can help with weight management for consumers and efforts by manufacturers to offer a choice of calorie levels in their products. Over the past few decades, there have been sporadic claims that low calorie sweeteners are associated with a range of adverse health effects such as cancer. As a result, consumers are unsure about their safety. The truth is that concerns about sweeteners and their link with cancer are not supported by well-controlled studies. According to the European Food Standards Agency (EFSA), approved low calorie sweeteners pose no threat to health provided that they are consumed within the acceptable daily intake level.
Are ‘superfoods’ really super?
The concept of the “superfood” has become very popular among the fitness minded people. We are surrounded by reports of ultra-healthy foods, such as pomegranates, beetroot, blueberries, cocoa and salmon. According to these reports, there is scientific evidence proving that eating these foods will give our bodies the health kick they need to stave off illness and ageing As a result public interest for this attractive “superfood” idea is huge. However, when looking at the evidence behind it, we need to be realistic about how this translates into real diets. Although certain components of foods and drinks may be particularly good for our health, it is unrealistic to expect a narrow range of “superfoods” to significantly improve our well-being. Instead we need to increase the range of nutritious foods in our diets and also include a variety of fruits and vegetables on a daily basis.
Nutrition myths are all around us, from bad foods that should be banned from our diet to shiny new superfoods and celebrity dieting techniques promising quick results and no effort. In order to distinguish dietary facts and fiction, it is important to look carefully at the scientific evidence behind the media’s claims. The main take home message is that moderation and variety in our diet combined with physical activity is and will always be the key to a healthy balanced lifestyle.
By Kleio Bathrellou