Eating only plants is called veganism when it extends to a full lifestyle, or a plant-based diet when the focus is purely on food choices. The two terms overlap but mean different things depending on who’s using them and why. A vegan eliminates all animal products from their life, including dairy, meat, poultry, fish, eggs, and honey, often for ethical or environmental reasons. Someone following a plant-based diet is making a dietary choice to eat mostly or entirely from plant sources, without necessarily adopting a broader philosophy about animal use.
Vegan, Plant-Based, and Whole Food Plant-Based
These three labels sit on a spectrum. A vegan diet excludes every animal product but places no restrictions on processed foods. You could eat vegan frozen meals, packaged snack foods, and sugary desserts all day and still technically qualify. A plant-based diet is a looser term that emphasizes plants as the foundation of your meals but leaves room for occasional animal products if you choose. Some people use “plant-based” simply because they find the word “vegan” too loaded.
A whole food plant-based diet (often shortened to WFPB) is the most specific version. It eliminates animal products and limits oils, added sugars, and processed foods. Everything you eat comes from whole grains, fruits, vegetables, legumes, nuts, and seeds in their minimally processed forms. Where a vegan might grab a frozen meat alternative, someone eating WFPB would get their protein from lentils or chickpeas and snack on nuts instead of packaged vegan cookies.
What About the Word “Herbivore”?
You might hear people jokingly call themselves herbivores. In biology, an herbivore is an organism that feeds on plants. There are even more specific terms: a folivore eats leaves and shoots, a frugivore specializes in fruit, and a xylophage eats wood. But these are ecological classifications for animals, not dietary labels for humans. Humans are physiologically omnivores, meaning our bodies can digest both plant and animal foods. Choosing to eat only plants is a dietary decision, not a biological category.
Health Benefits of Eating Only Plants
A plant-exclusive diet can meaningfully shift several health markers. People following vegetarian or vegan diets see average drops in total cholesterol of about 7%, LDL (“bad”) cholesterol of 10%, and apolipoprotein B (a protein linked to heart disease risk) of 14% compared to omnivores. Those reductions come largely from cutting out saturated fat found in meat and dairy while increasing fiber intake from whole grains, legumes, and vegetables.
Blood sugar regulation also tends to improve. Fiber slows the absorption of glucose in the intestines, preventing the sharp spikes that stress your body’s insulin response. Plant foods are rich in antioxidants like flavonoids and carotenoids that reduce the chronic inflammation known to impair how insulin works. The gut microbiome shifts too: plant-heavy diets promote the growth of beneficial bacteria that support metabolic processes. And because plant-based eaters tend to carry less body weight, particularly less abdominal fat, they face a lower risk of insulin resistance overall.
Nutrients That Need Extra Attention
Eliminating animal products removes the most bioavailable sources of several key nutrients. Planning around these gaps is the practical reality of eating only plants.
Vitamin B12
This is the one nutrient you simply cannot get from whole plant foods. The recommended daily intake is 2.4 micrograms, and studies show that up to 86% of vegans have blood levels below the recommended range. B12 is essential for nerve function and red blood cell production, so supplementation or fortified foods (like nutritional yeast, fortified plant milks, or fortified cereals) are non-negotiable on a fully plant-based diet.
Iron
Plants contain non-heme iron, which your body absorbs less efficiently than the heme iron in meat. Compounds called phytates, found in whole grains, bran, and legumes, further inhibit iron absorption. Research in the American Journal of Clinical Nutrition confirmed that phytates are the main cause of bran’s inhibitory effect on iron uptake. The practical workaround is pairing iron-rich foods (spinach, lentils, tofu) with vitamin C sources like citrus, bell peppers, or tomatoes, which boost non-heme iron absorption significantly.
Calcium
Adults need 1,000 mg of calcium daily (1,200 mg for women over 50 and men over 70). Without dairy, you need to be intentional about plant sources. Frozen collard greens pack about 360 mg per cup. Broccoli rabe delivers 200 mg, frozen kale provides 180 mg, and cooked bok choy offers 160 mg. Fortified plant milks (almond, soy, oat) typically contain around 300 mg per cup, roughly matching cow’s milk. Tofu prepared with calcium adds about 205 mg per serving. Hitting your daily target is realistic but requires choosing these foods consistently.
Protein
Getting enough total protein on a plant-based diet is straightforward. Getting the same quality of protein takes a bit more thought. Protein quality is measured by how well your body can digest and use it. Soy scores highest among plant proteins, approaching the level of milk protein. But many common plant sources score considerably lower: quinoa sits around 68 on the standard scale, oat protein ranges from 45 to 60, rice comes in at 54, and almond protein scores just 30. The fix is variety. Combining legumes with grains, eating soy-based foods regularly, and mixing protein sources throughout the day ensures you get the full range of amino acids your body needs.
How People Make It Work Day to Day
The practical side of eating only plants comes down to building meals around five categories: plant protein (beans, lentils, tofu, tempeh), whole grains (brown rice, quinoa, oats), vegetables, fruits, and plant-based fats (nuts, seeds, avocado). Most people who stick with it long-term describe a learning curve of a few weeks as they figure out new staple meals, followed by a rhythm that feels just as automatic as their previous way of eating.
A daily B12 supplement, attention to iron and calcium sources, and varied protein choices cover the nutritional bases. The rest is largely about discovering which plant foods you actually enjoy cooking and eating, since that determines whether the diet lasts a month or a lifetime.