PETALING JAYA: With the hype over the benefits of a vegetarian diet, many have jumped onto the bandwagon without further thought.
Though a vegetarian diet does offer quite a few benefits, there are certain pitfalls to avoid, advises dietitian Ngoh Hooi Jiun.
What is a diet that contributes to health?
Ngoh: A balanced, wholesome plant-based diet offers many health benefits. Whole grains,
vegetables, fruits, legumes, seeds and nuts are naturally rich in vitamins and minerals and are essential to maintaining good health.
Consumption of processed food, fats and refined sugars should be kept to a minimum.
Does becoming a vegetarian help you become healthy?
Ngoh: A vegetarian consumes plant-based food and excludes any animal products.
Consumption of nutrient-dense food with minimal processed plant-based food should be encouraged for optimal health.
It also benefits those who are obese, have type 2 diabetes, high blood pressure, lipid disorders and cardiovascular diseases.
Generally, a vegetarian consumes lower portions of calories from saturated fat and more fibre, potassium and vitamin C than non-vegetarians.
Some people think that being a vegetarian is healthier. Is this true?
Ngoh: Positive health outcomes have been identified among vegetarians. In 2009, the American Dietetic Association’s position paper on vegetarian diets stated that vegetarian diets are associated with lower BMI, cholesterol, heart disease, type 2 diabetes, blood pressure and cancer risk.
By swapping meat and other animal products for more beans, legumes, nuts, seeds, vegetables and fruits, people are not only losing weight but decreasing their risk of getting chronic diseases.
We cannot cure chronic diseases, but we may be able to prevent and control them by changing how we eat.
What types of vegetarian diets are healthy and what are those that are not healthy and we should avoid? Is vegetarian ‘imitation meat’ healthy?
Ngoh: A healthy vegetarian diet should be wholesome and include a variety of whole grains, vegetables, fruits, beans, legumes, seeds and nuts.
People should avoid excessively processed and packaged vegetarian food that is high in fat, sodium and refined sugar.
Likewise, food loaded with additives, colouring and preservatives should be restricted.
Imitation meats are usually added with flavour enhancers, colouring substances, leavening agents and emulsifiers for better taste, appearance and texture of food.
People often choose to eat imitation meat as they move from a meat-based diet to a plant-based diet, such as soy-based meat substitutes.
Long-term consumption of imitation meat is not encouraged as it is highly processed and may not be as healthy as wholesome food.
Are there nutrients that vegetarians lack, and what are they? What should vegetarians do to ensure that they get adequate vitamins and minerals?
Ngoh: Vegetarians are susceptible to certain vitamin deficiencies – vitamin B12, vitamin D, calcium, iron and omega-3 fatty acids.
Those who are very young, pregnant, lactating, elderly, or who suffer from poverty and disease are at a higher risk of nutrient deficiency.
It is recommended that vegetarians take vitamin B12 supplements or foods fortified with vitamin B12 since there are no known plant foods that have natural sources of vitamin B12.
Vitamin D deficiency is also a concern since vegetarians exclude animal products, which are generally a good source of vitamin D.
They need to consume vitamin D fortified food or take vitamin D supplements and get adequate sun exposure for vitamin D.
Vegetarians may also suffer calcium deficiency and are at risk of impaired bone mineralisation and fractures, so they should choose calcium-fortified tofu, soy milk, tempeh, as well as legumes, green leafy vegetables, almonds and sesame seeds to meet their daily requirements.
If they are not eating calcium-rich food adequately, calcium supplements are recommended.
Since vegetarians do not eat meat, poultry and seafood, they also risk not consuming or absorbing adequate iron.
In animal foods, iron is often attached to proteins called heme proteins, which is referred to as heme iron. In plant food, iron is not attached to heme proteins; so plant-based iron is classified as non-heme iron.
The human body does not absorb as much non-heme iron from plant food compared with heme iron from animal products.
It is recommended that vegetarians use a cast-iron skillet for cooking to boost iron intake, and eat vitamin C-rich food for better iron absorption.
Vegetarians may also be deficient in omega-3 fatty acids. They should eat food rich in omega-3 fatty acids such as flaxseeds, walnuts and canola oil.
DHA and EPA supplements derived from microalgae are also good alternatives.
What is the risk of vegetarians suffering hair loss?
Ngoh: Vegetarians, especially vegans, are at risk of deficiency of vitamin B12, zinc and iron if the diet is not carefully planned.
The most significant health issue from these nutrient deficiencies is hair loss.
It’s normal to lose 100 to 200 strands of hair per day. Anything more indicates excessive hair loss that may be due to inadequate nutrient intake.
Vegans tend to lack vitamin B12 because vitamin B12 is only available in meat, fish, poultry and other food from animal sources.
Insufficient intake of vitamin B12 leads to scaly scalp and hair loss.
Inadequate intake of zinc from a vegan diet that excludes good sources of zinc such as oysters, red meat and chicken results in hair loss and hair that is unruly, with dull strands.
Vegans also face the risk of not consuming or absorbing adequate iron. Iron deficiency can lead to hair loss, fatigue and weakness.
Another concern is taking too much soy and soy products, which are goitrogenic and can aggravate hypothyroidism. A symptom of hypothyroidism is excessive hair loss.
Is being vegetarian for everyone?
Ngoh: People may adopt a vegetarian diet due to ethical or religious reasons, want to improve health, or desire a more sustainable environment.
Vegetarian diets are suitable for everyone, but patients with kidney disease may need to restrict plant foods that are high in potassium and phosphorus, if indicated by elevated serum levels.
Patients with thyroid disease should be cautious about consuming plant foods that are goitrogenic, such as soy products and cruciferous vegetables, and the patient should be advised to cook these vegetables to inactivate goitrogens.
What about those who suffer from irritable bowel syndrome (IBS) or inflammatory bowel disease such as Crohn’s disease who cannot take too much fibre? Can they be vegetarians?
Ngoh: Foods that trigger symptoms differ for each person with IBS and Crohn’s disease. Identify your own “trigger foods”. By avoiding your trigger foods, you may find gastrointestinal symptoms more manageable.
If certain raw vegetables cause symptoms to flare, you don’t necessary give them up. Try steaming, boiling, or stewing the vegetables as this will make it more tolerable for the gut.
Do you have any other observations, comments and advice about being a vegetarian?
Ngoh: Being a healthy vegetarian is simple – eat more whole, unprocessed foods that come directly from plants.
Meanwhile, use less fat and sodium when cooking. Control portion size to avoid overeating.
To move towards a plant-based diet, it is important to get a dietitian to guide you on preparing simple meals because a carefully planned diet will ensure one gets adequate nutrients and adhere to long-term healthy dietary practices.
Can you share some tips for moving towards a plant-based diet?
Ngoh: Start slow. Try one meatless meal a week. Include legumes, beans and tofu in one’s diet as meat substitutes.
Become semi-vegetarian in-between the stages of a meat-based diet and a plant-based diet.
Replace some of the meat with legumes. For example, add half the amount of chicken usually eaten and top up with peas.
Choose whole grains more than processed white varieties. For example, eat whole grain rice and wholemeal bread. Eat a variety of fresh vegetables and fruits of various colours.
Did you find this article insightful?