From the Guidelines
A well-planned vegetarian diet can be nutritionally complete, providing all necessary nutrients for optimal health, as long as it includes a variety of plant-based foods and attention is paid to key nutrients like vitamin B12, iron, zinc, and omega-3 fatty acids. According to the most recent and highest quality study, 1, a vegetarian diet can meet protein needs if a variety of foods are consumed and energy needs are met. The study suggests that protein intake at the low end of the Acceptable Macronutrient Distribution Range (AMDR) should be considered more than adequate.
Key points to consider for a nutritionally complete vegetarian diet include:
- Consuming a variety of plant-based foods, including fruits, vegetables, whole grains, legumes, nuts, and seeds
- Paying special attention to nutrients more commonly found in animal products, such as:
- Vitamin B12, which can be obtained through fortified foods or supplements
- Iron, which can be found in legumes, nuts, and seeds
- Zinc, which is abundant in legumes, nuts, and seeds
- Omega-3 fatty acids, which can be found in nuts and seeds
- Ensuring adequate protein intake, which can be achieved by consuming a variety of protein-containing foods throughout the day, without specifically trying to ensure that protein sources complement one another.
Overall, with proper planning and attention to these key nutrients, a vegetarian diet can meet all nutritional needs and support overall health and well-being, as supported by studies such as 1, which provides the most recent and highest quality evidence on this topic.
From the Research
Nutritional Completeness of Vegetarian Diets
- A well-planned vegetarian diet can be nutritionally complete and provide all the necessary nutrients for good health 2, 3, 4.
- Vegetarian diets can meet current recommendations for all essential nutrients, including protein, n-3 fatty acids, iron, zinc, iodine, calcium, and vitamins D and B-12 2, 3.
- A vegetarian diet typically provides a low intake of saturated fat and cholesterol and a high intake of dietary fiber and many health-promoting phytochemicals 3, 4.
- Vegetarians tend to have lower body mass index, serum total and low-density lipoprotein cholesterol levels, and blood pressure, and reduced rates of death from ischemic heart disease, hypertension, stroke, type 2 diabetes, and certain cancers compared to non-vegetarians 2, 3, 4, 5.
Key Nutrients in Vegetarian Diets
- Protein intake may be lower in people following plant-based diets, but it is still within recommended intake levels 6.
- Fiber, polyunsaturated fatty acids, folate, vitamin C, E, and magnesium intake tend to be higher in vegetarians and vegans compared to meat-eaters 6.
- Intake and status of vitamin B12, vitamin D, iron, zinc, iodine, calcium, and bone turnover markers may be lower in plant-based dietary patterns compared to meat-eaters 6.
- Vegans may require reliable sources of vitamin B-12, such as fortified foods or supplements 4.
Health Benefits of Vegetarian Diets
- Vegetarian diets have been associated with a lower risk of certain types of cancer, overall cancer, overweight-obesity, type 2 diabetes, dyslipidemia, hypertension, and vascular diseases 5.
- A well-planned vegetarian diet can promote health and lower the risk of major chronic diseases 2, 3, 4.
- The beneficial effects of a vegetarian diet on health have been reported in both observational and intervention studies 5.