Vegan Diet Weakness: Nutritional Deficiency Or Misinformation?

A vegan diet can be a healthy choice, but it's not foolproof. One common complaint is that people often feel weak or tired. This could be due to a number of reasons, such as not consuming enough calories, a lack of vitamins and minerals like B12 and iron, or even underlying medical conditions. It's important to consult a healthcare professional if you're experiencing these symptoms, as they can advise on dietary changes or supplements to ensure you're getting the proper nutrition.

Not eating enough calories

One of the most common reasons for feeling weak on a vegan diet is not consuming enough calories. This can happen because plant-based foods tend to be less calorie-dense than animal products, so you may need to eat more volume or higher-calorie foods to meet your energy needs. It's important to ensure that you're eating enough calories to cover your Basal Metabolic Rate (BMR) and your Active Metabolic Rate (AMR). Your BMR is the number of calories your body needs for basic functions like breathing and pumping blood, while your AMR includes the calories needed for daily activities and exercise.

To calculate your BMR, you can use the following formulas:

• For men: BMR = 88.362 + (13.397 x weight in kg) + (4.799 x height in cm) – (5.677 x age in years)
• For women: BMR = 447.593 + (9.247 x weight in kg) + (3.098 x height in cm) – (4.330 x age in years)

You can then multiply your BMR by the appropriate AMR factor based on your activity level:

• Sedentary (little or no exercise): AMR = BMR x 1.2
• Lightly active (exercise 1–3 days/week): AMR = BMR x 1.375
• Moderately active (exercise 3–5 days/week): AMR = BMR x 1.55
• Active (exercise 6–7 days/week): AMR = BMR x 1.725
• Very active (hard exercise 6–7 days/week): AMR = BMR x 1.9

It's recommended to track your calorie intake for a few days to ensure that you're meeting your energy needs. If you're not eating enough, gradually increase your portion sizes and focus on including more calorie-dense plant-based foods in your diet. Some examples of calorie-dense vegan foods include nuts, seeds, nut butters, tahini, tofu, tempeh, whole grains, lentils, and avocados. Cooking with extra virgin olive oil can also help increase the calorie content of your meals.

Additionally, including a smoothie as a snack between meals can be an easy way to boost your calorie intake. You can add ingredients like nut butter, fruit, oats, and flaxseeds/chia seeds to increase the calorie content.

It's important to note that feeling weak on a vegan diet can also be due to other factors such as nutrient deficiencies, inadequate sleep, or overexercising. If you're concerned about your health or nutrition, it's always best to consult with a healthcare professional or a registered dietitian.

Lack of vitamin B12

Vitamin B12 is required for cell division, and deficiency can cause abnormally large red blood cells to appear in the blood, a condition called megaloblastic anaemia. This results in a decreased ability of the blood to carry oxygen, leading to fatigue, weakness, decreased stamina, shortness of breath, and even palpitations. Vitamin B12 is also required for the function of nerve cells, the spinal cord, and the brain. Deficiency can therefore result in mental changes including confusion, depression, irritability, insomnia, and poor concentration.

Vitamin B12 is made by microorganisms in an animal's intestines or diet, but humans are not able to produce it themselves. While plants are also unable to make vitamin B12, there are some instances of fermented foods containing it due to the bacteria used in their production.

The recommended daily intake of vitamin B12 for adults and teenagers is 2.4 micrograms per day. Vegans can obtain this amount by eating fortified foods two or three times a day to get at least three micrograms of B12, taking a daily supplement of at least 10 micrograms, or taking a weekly supplement of at least 2000 micrograms.

Some plant-based foods that are fortified with vitamin B12 include:

• Nutritional yeast
• Fortified plant-based milk
• Fortified breakfast cereals

In addition to fortified foods, vegans can also obtain vitamin B12 from natural sources such as:

• Nutritional yeast
• Certain mushrooms
• Some algae

Lack of iron

Iron is an essential mineral for proper growth and development. It is required for the transportation of oxygen around the body and is found in red blood cells called haemoglobin. Myoglobin, a protein made by iron, brings oxygen to your muscles.

Iron deficiency can lead to a condition called iron deficiency anaemia, which can cause fatigue, dizziness, and heart palpitations. This occurs when the body doesn't have enough iron to produce haemoglobin, which binds and carries oxygen in the blood.

The recommended daily intake of iron is 18 milligrams, but the National Institute for Health recommends that vegetarians and vegans consume 1.8 times the normal RDI, or about 32 grams. This is because vegans consume non-heme iron, which is not absorbed as efficiently as heme iron, derived from animal sources.

If you think you may be deficient in iron, consult your doctor, who can perform a simple blood test to check your iron levels.

To increase your iron intake, try adding the following iron-rich foods to your diet:

• Whole wheat bread, cereals, pasta, quinoa, and oatmeal
• Cooked spinach, asparagus, and green beans
• Beans, legumes, soybeans, tofu, and lentils
• Dried apricots, raisins, and dates
• Blackstrap molasses
• Nuts and seeds
• Iron-fortified products

Pairing these foods with vitamin C will also enhance your body's ability to absorb iron. Good sources of vitamin C include:

• Citrus fruits and juices
• Red and green bell peppers
• Kiwi, strawberries, tomatoes, cantaloupe, and papaya

Lack of vitamin C

A vegan diet can be a healthy choice, with numerous health organisations endorsing the adoption of this dietary pattern. However, it is important to be mindful of consuming a balanced diet to ensure you are getting all the necessary nutrients.

Vitamin C is one such vital nutrient, and a deficiency can lead to feelings of fatigue and weakness. Vitamin C plays a critical role in collagen production, which is essential for healthy skin, hair, joints, bones, and blood vessels. A deficiency can cause impaired collagen production, resulting in rough, bumpy skin, and abnormal hair growth. In addition, vitamin C is necessary for the absorption of iron, which is another nutrient that contributes to energy levels.

To ensure adequate vitamin C intake, aim to include a variety of citrus fruits and juices, such as oranges, lemons, and grapefruits, in your diet. Other good sources of vitamin C include kiwis, broccoli, and parsley. By including these foods in your diet, you can help prevent a vitamin C deficiency and maintain your energy levels while following a vegan diet.

It is worth noting that cooking can destroy some of the vitamin C content in food, so it is recommended to consume fresh fruits and vegetables to ensure adequate intake. Additionally, vitamin C is water-soluble, and the body does not store large amounts, so it is important to include sources of this vitamin in your diet every day.

Lack of vitamin D

Vitamin D is essential for maintaining healthy bones, as it helps the body absorb calcium and phosphorous from food. A deficiency in vitamin D can lead to weak and brittle bones. In addition, vitamin D is necessary for a well-functioning immune system, and a lack of it can increase the risk of infections and autoimmune issues.

Vitamin D is typically derived from animal products such as salmon, egg yolks, and shellfish, which are not vegan-friendly. However, vegans can get their vitamin D from fortified foods such as soy milk, orange juice, almond milk, and rice milk. Vitamin D-fortified breakfast cereals and oatmeal are also good sources.

Mushrooms are one of the few non-animal sources of vitamin D. Mushrooms exposed to ultraviolet light when growing can contain about 450 IU per 100-gram serving.

Vitamin D can also be obtained by spending time in the sun. Exposing your skin to sunlight allows your body to convert cholesterol into vitamin D. Spending 10 to 30 minutes in the sun three times a week is usually sufficient for most people. However, those with darker skin may require more sun exposure.

Vitamin D supplements are another option for vegans to boost their intake. It is important to note that not all vitamin D supplements are vegan-friendly, so it is essential to research the brand before purchasing.

The recommended daily intake of vitamin D varies depending on age. For adults 70 and under, the recommended intake is 600 IU, while for adults over 70, it is 800 IU.

If you feel weak on a vegan diet, it may be a good idea to consult a healthcare professional to determine if a vitamin D deficiency or any other nutritional deficiencies are the cause.

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