Going vegan: Why an exclusively plant-based diet is unbalanced
Many other lifestyle changes we can make will have a positive impact on the planet
A vegan diet is not nutritionally complete, requires supplements and a good knowledge base to implement effectively. Photograph: iStock
Research shows people are becoming more aware of how their eating habits impact on their health and on our planet. Health and environment are two drivers increasing the number of people following a vegan diet.
A diet based on plants is called a plant-based diet. For some people, this will include animal produce, for others it will completely exclude animal produce.
A vegan diet is 100 per cent plant-based.
What is important for people to know prior to embarking on a vegan diet is that it is not nutritionally complete. The nutritional gaps within this diet include vitamin B12, vitamin D and omega 3. Other nutritional gaps can occur if the person doesn’t have the necessary knowledge to balance the diet appropriately. For example, they need to know how to eat to obtain optimal levels of protein at each meal and how to ensure adequate daily intakes of particular nutrients such as iron and iodine.
Even when the diet is balanced, supplements need to be taken. It is challenging to know if the nutritional gaps have been plugged for three main reasons.
1. There are only a few vitamins and minerals that can be checked by your GP when they take your blood. It is not a complete list. Therefore, nutritional gaps cannot be plugged if they are not known to exist.
2. We cannot supplement the unknown unknowns. Nutrition is a science that is gathering information with time. We cannot plug gaps for nutrients that we do not know exist. This is the same for everybody, regardless of dietary patterns. However, as a vegan diet requires the removal of so many foods from the diet, the risk is greater.
3. Generally speaking, a supplement is not as effective as eating the nutrient through food. For example, calcium from dairy has a significantly greater impact on bone mineral density than calcium via a supplement. The reasons for this are plentiful but include what is called the ‘food matrix’. The food matrix is how all the nutrients within a food work together to support the health of the human body. A food is greater than the sum of its parts. Calcium is one example, but the same has been shown with other popular supplements such as omega 3.
The other motivational factor for following a vegan diet is the positive impact it can have on the planet. Food production contributes to greenhouse gas emissions and therefore contributes to global warming. It’s important to recognise that all stages of food production impact on the environment, including growing, harvesting, fisheries, livestock, processing and packaging, distribution, retail, cooking and eating, waste, recycling and landfills. A sustainable diet must meet the nutritional needs of the present and future generations and can target any point in the food production line.
A vegan diet is not nutritionally complete, requires supplements and a good knowledge base to implement effectively. It is one way to eat more sustainably but it is not the only way. Perhaps it may be preferable for some people to reshape their current diet for environmental goals without running the risk of following an unbalanced diet, leading to consequences to their health.
Following a more sustainable lifestyle requires behaviour change, which will lead to varying levels of alterations among the population. For some people, it may be focusing on Irish produce. For example, Irish beef is a more sustainable choice than beef from another country due to the environmental cost of distribution and depending on the country, adherence to sustainable farming methods. For others, they may wish to focus on reducing food waste, as 60 per cent is considered to be avoidable.
There are many options for an individual to consider, which include eating a wider variety of foods, eating more legumes, nuts and seeds, trying to avoid eating to excess, reducing alcohol, reducing sugar-sweetened beverages, avoiding processed foods, eating fish from certified fisheries, focusing on water as the main beverage and eating all parts of the animal instead of the more popular cuts. To follow a more sustainable lifestyle, some people may choose to not make any changes to their diet.
However, if they drive their car less and avoid air travel where possible, the positive impact they are having on the environment may be greater than the sum of all dietary changes. There are so many ways in which we can change our lifestyle to have a positive impact on the future of the planet.
Following a vegan diet is not the only route to take.
Orla Walsh is a qualified dietitian and member of the Irish Nutrition and Dietetic Institute (MINDI) and Self Employed Dietitians of Ireland (SEDI).
This article was amended on November 18th to include links to relevant research.