#vegannutrition Archives - Plant Nutrition & Wellness

Vegan Zinc – Sources, Absorption, and Deficiency

Posted on July 31, 2020August 29, 2022 by frans

Why zinc is important for vegans

Zinc is an essential nutrient to consider when following a vegan or vegetarian diet. It is a mineral that is distributed throughout all our body tissues and fluids. It is necessary for our body to perform a variety of important functions (1).

Some of these include:

Immune support and wound healing
Metabolism
Regulation of gene expression and DNA synthesis
Supports normal growth and development during childhood, adolescence, and pregnancy

Zinc requirements for vegans

Those following a vegetarian or vegan diet have higher requirements for certain vitamins and minerals than those specified for the general healthy population. These include the minerals iron and zinc.

Zinc is one of these nutrients as plant-based sources have a lower bioavailability than animal-based sources such as red meat and dairy. In other words, it is harder for our bodies to absorb this nutrient from plant-based foods.

It is recommended that those following a vegan/vegetarian or predominantly plant-based diet consume 150% of the recommended daily intake for the general population to ensure requirements are met.

Below is a summary of the daily requirements for vegetarians/vegans based on 150% of the values provided in the Nutrient Reference Values for Australians and New Zealanders(2).

There is no difference in the RDI between older adults (70 years+) and those in their early stages of adulthood. See zinc requirements for those following a non-vegetarian or vegan diet here (4).

Want to make sure that you’re always getting enough zinc in your diet? Why not try one of our male or female vegan meal plans!

Best vegan sources of zinc

Zinc is present in a variety of plant-based foods. A well-planned vegetarian or vegan diet is more than adequate to meet your requirements.

It can be found in high concentrations in the outer layers of grains. As such, the best plant-based sources are minimally refined wholegrain products such as rolled oats, brown rice, and wholegrain bread and cereals.

Vegan zinc sources include nuts and seeds, legumes, soy products such as tofu and fortified breakfast cereals(1).

The following table lists the amounts found in different plant-based foods (3):

It is recommended that you include a variety of these foods in your diet on a daily basis.

This may look like:

Breakfast: ~4mg

½ cup oats + 1 cup soymilk + 30g pumpkin seeds + berries

Lunch: ~6mg

2 slices wholegrain bread + 2 tbsp hummus + ½ cup salad + 15g sundried tomato + 100g sliced tempeh

Dinner: ~6.5mg

Tofu stir fry (with 150g tofu, 30g cashews, 2 cups mixed vegetables) + ½ cup brown rice

Snacks: ~5mg

30g pecans, 1 apple, hot chocolate (2tbsp cocoa, 1cup soymilk, 1tsp sugar), 4 wholegrain crackers + 2tbsp tahini + tomato

TOTAL: 21.5mg total

Optimising zinc absorption

Plant-based sources of zinc are not as readily absorbed by the body. This is due to the presence of inhibiting compounds in foods that reduce absorption.

The main inhibitors are phytates which are commonly found in wholegrains and legumes.

This effect can be overcome by food-processing techniques such as the fermentation of whole grains and soaking legumes and sprouting seeds and grains.

Additionally, taking iron supplements close to meals can also inhibit the absorption of zinc as the two nutrients compete for uptake (1,4).

Foods that contain high amounts of protein are also a good choice to consider as protein binds to zinc and increase zinc absorption.

Read about meeting your protein needs on a vegan diet here

Some simple ways to improve vegan zinc absorption include:

Opting for yeast-leavened or sourdough bread
Pre-soak and rinse legumes before cooking
Opting for sprouted grains and seeds
Consume iron supplements away from meals
Include foods high in both zinc and protein such as legumes, tofu, tempeh and nuts

Signs of a zinc deficiency

Cases of deficiencies are rare in developed countries due to our abundance of access to zinc-rich foods however they are still possible.

The main reasons for developing a deficiency include poor dietary availability paired with an increased requirement during periods of growth and development or periods of stress, infection and acute trauma(2).

Signs of a deficiency to look out for include:

Reduced growth rate in children
Suboptimal pregnancy outcomes
Increased susceptibility to illness and infections
Poor wound healing
Impaired taste perception

Is being vegan a risk factor for developing a zinc deficiency?

No, despite differences in food choices, vegetarians and vegans tend to have similar blood levels of zinc to non-vegetarians.

Over time, the body is able to adapt to the lower bioavailability of zinc in plant-based diets by increasing the efficiency in which it is able to absorb this mineral and reducing losses out of the body. Therefore, those following a plant-based diet are at no greater risk (1).

If you are concerned you may have a zinc deficiency it is important to discuss any concerns with your GP.

Should vegans supplement zinc?

It is absolutely possible to meet your requirements from solely food sources when following a plant-based or vegan diet. This is always preferred over supplement use.

Whilst there is no evidence of adverse effects from consuming high amounts of zinc naturally occurring in food, excess zinc intake from long term high doses of zinc supplements may result in negative side effects. This includes negatively affecting the immune system , lowering HDL (also known as good cholesterol) levels and copper deficiency.

There are a variety of forms of zinc available in supplements. These include zinc acetate, sulfate, picolinate, monomethionine, gluconate, glycinate, orotate and citrate.

There is an upper limit of total zinc intake of 40mg/day from food and supplements (including fortified foods) and any supplementation should proceed with caution(2).

To reduce the risk of having excess zinc supplementation, it is important to seek medical advice from your GP before commencing and supplements.

References

If you’re following a plant-based or vegan diet and want to make sure you’re meeting all your nutritional needs, take control and apply to work with one of our expert plant-based dietitians. .

This blog was co-written by student dietitian by Georgia D’Andrea. You can connect with Georgia on Linkedin.

Lectins Myths: Are They Harmful To Your Health?

Posted on February 3, 2020July 29, 2022 by frans

Lectins are an “anti-nutrient” that have received a lot of media attention recently. Fad diet books cite this food component as one of the central causes of obesity, chronic inflammation, and autoimmune conditions.

I actually find this slightly ironic, because when we look at where lectins come from, they’re all from plant-based foods. But if we actually look at the statistics of how much Australian’s eat plant-based foods, 95% of adults aren’t actually meeting the fruit and vegetable recommendations.

So the claims that lectins are the cause of all of these diseases already isn’t making sense (1).

In this article we take a look at some of the lectins myths – are they harmful, should we avoid them and do they cause inflammation.

What are lectins?

Lectins are a protein found in plant foods that bind to carbohydrates. They resist being broken down in the gut and are stable in acidic environments (such as our stomach). This is actually a feature that helps to protect lectic-containing plants in nature (2).

What foods contain lectins?

Lectins are found in varying amounts in most plants. This includes beans, pulses, grains, fruits and vegetables, nuts, coffee, chocolate some herbs and spices. Pulses (think chickpeas, lentils, kidney beans) and grains (like rice and quinoa) contain the highest amount compared with other foods.

Why are they a problem?

When consumed, lectins can cause negative side effects. One of the most commonly reported reaction is found when eating raw or uncooked kidney beans. Kidney beans contain a type of lectic called phytohaemagglutinin. Ingestion of this can cause red blood cells to clump together as well as nausea, vomiting, stomach upset and diarrhea (3).

Lectins have also been shown to interfere with the absorption of minerals including iron, calcium, phosphorus, and zinc.

Some research has also indicated that they may bind to the cells lining the digestive tract. Over time, this may effect the intestinal flora and is theorized to play a role in inflammatory conditions such as type 1 diabetes and rheumatoid arthritis (3,4).

That sounds pretty bad, should I be worried?

Unsurprisingly, these theories have fuelled the profits of books and enzyme supplements from the anti-lectin movement. There is very limited research in humans about the number of active lectins consumed in the diet and their long term health effects.

Lectins in foods are most often studied in developing countries where there is high levels of malnutrition, limited cooking facilities and lack of dietary variety (5,6).

There are different forms of lectins found in different foods. The reactions people have to them vary significantly.

Some people with digestive conditions such as Irritable Bowel Syndrome may be more likely to experience some negative symptoms from lectins and other anti-nutrients. However, a reasonable suggestion is simply to eat less of the food causing the digestive problem (ps. see a dietitian to help you with this).

Do they have any benefits?

Lectins can also act as a powerful antioxidant. Antioxidants help to protect cells from damaging unpaired electrons known as free radicals. This antinutrient can also help slow down the digestion and absorption of carbohydrates. This helps to stabilise blood sugar levels and keeps you fuller for longer.

Emerging research has also looked into the beneficial effect low amounts of lectins on stimulating gut cell growth in patients who are unable to eat for long periods (3,7)

Researchers are also investigating the effects that lectins may have in the treatment of cancer and even could be used in antitumor drugs in the future (8).

In addition to this, research time and time again continues to show the benefits of eating whole grains and legumes. People who consume more whole grains have improved cardiovascular health outcomes. Eating legumes such as chickpeas, lentils and kidney beans are linked with supporting healthy body weight and reducing CRP inflammatory markers.

Preparing food to minimise lectins

It is quite rare to eat foods with a high amount of lectins. This is due to them being most potent in the raw state of foods and these foods not typically consumed raw.

When foods are cooked, especially at high heat using a liquid such as cooking, stewing, boiling or soaking, this inactivates most lectins. They are also water-soluble and found on the outer surface of the food. This means, when these foods are cooked, the exposure to water removes the lectins.

The body also has a fantastic ability to produce enzymes during digestion that helps to break them down.

When cooking beans in a crock pot, use canned beans or boil them for at least 30 minutes before putting in the crockpot.

The bottom line

Just don’t eat grains and legumes raw.

Lectins are certainly harmful when consumed. However, given that they are denatured during cooking and the evidence against limiting these foods from our diet is very weak, it is definitely not something to be concerned about. Just make sure to cook your food!

There is strong evidence supporting the health benefits of pulses, grains, nuts, fruits and vegetables (i.e even in foods where lectins are found). If removed in a “lectin-free” diet, this could potentially lead to nutritional deficiencies.

If you’re following a plant-based or vegan diet and experiencing digestive upset, take control and apply to work with one of our expert plant-based dietitians. .

References

1. 4364.0.55.001 – National Health Survey: First Results, 2014-15. (2020). Retrieved 3 February 2020, from https://www.abs.gov.au/ausstats/abs@.nsf/Lookup/by%20Subject/4364.0.55.001~2014-15~Main%20Features~Daily%20intake%20of%20fruit%20and%20vegetables~28

2. Peumans, W., & Van Damme, E. (1995). Lectins as Plant Defense Proteins. Plant Physiology, 109(2), 347-352. doi: 10.1104/pp.109.2.347

3.Vasconcelos, I., & Oliveira, J. (2004). Antinutritional properties of plant lectins. Toxicon, 44(4), 385-403. doi: 10.1016/j.toxicon.2004.05.005

4. Freed, D. (1999). Do dietary lectins cause disease?. BMJ, 318(7190), 1023-1024. doi: 10.1136/bmj.318.7190.1023

5. Gibson, R., Bailey, K., Gibbs, M., & Ferguson, E. (2010). A Review of Phytate, Iron, Zinc, and Calcium Concentrations in Plant-Based Complementary Foods Used in Low-Income Countries and Implications for Bioavailability. Food And Nutrition Bulletin, 31(2_suppl2), S134-S146. doi: 10.1177/15648265100312s206

6. Roos, N., Sørensen, J., Sørensen, H., Rasmussen, S., Briend, A., Yang, Z., & Huffman, S. (2012). Screening for anti-nutritional compounds in complementary foods and food aid products for infants and young children. Maternal & Child Nutrition, 9, 47-71. doi: 10.1111/j.1740-8709.2012.00449.x

7. Liu, Z., Luo, Y., Zhou, T., & Zhang, W. (2013). Could plant lectins become promising anti-tumour drugs for causing autophagic cell death?. Cell Proliferation, n/a-n/a. doi: 10.1111/cpr.12054

8.Sarup Singh, R., Preet Kaur, H., & Rakesh Kanwar, J. (2016). Mushroom Lectins as Promising Anticancer Substances. Current Protein & Peptide Science, 17(8), 797-807. doi: 10.2174/1389203717666160226144741

Do Vegans Need To Use Protein Powder?

Posted on April 22, 2019July 29, 2022 by frans

One of the most common questions asked to people following a vegan diet is “where do you get your protein from?”. Understandably, this can be incredibly frustrating and may even leave you double-guessing whether or not you are consuming enough. In this article, we explore some sources of plant-based protein and ask the question – do vegans need to use protein powder?

What is protein?

Protein is a key nutrient in the human body, it is responsible for muscle maintenance, key regulatory systems like hormone production, wound healing and fighting infection [1] It is also a bit of a nutrition ‘buzz-word’, due to all of the fitness influencers on social media.

What are sources of plant based proteins?

The main sources of vegan protein include (but are not limited to); legumes (including beans, peas, lentils and pulses), nuts and seeds (including pastes, butters etc), tofu, tempeh, quinoa and of course protein powders. These vary in protein content from about 5g per serve to 14g per serve [2].

Serve size is dependent on the type of protein source, for example, one serve legumes is equal to 1 cup vs 1 serve of nuts, which is equal to only 30g (a small handful) [3].

It is important to note here that on social media you are likely to find a lot of information about protein content comparisons of foods “per 100 calories”. Though this information may not be incorrect, it has been taken out of context and therefore can be quite misleading.

For example, it is misleading to say that 100 calories of broccoli (this is a classic example circulating online) is comparable, in any sense, to 100 calories of meat. Why? Because 100 calories is 2 or more cups of broccoli compared to only a few mouthfuls of meat [2].

What this means is that if you’re trying to be conscious of your protein on a plant-based diet, broccoli is probably not going to be your preferred source unless your would like to have many cups of broccoli every day. I could go on further about why this is misleading, but I think you get the picture.

What if I don’t like vegan proteins like beans?

You could try eating a variety of different protein sources. This will not only ensure you are consuming enough protein, it will also mean that you are obtaining all of the essential amino acids across the day and week,

Amino acids are the smaller components that proteins are made of. Different sources of protein contain different amino acids[1].

This will also mean that you are less likely to get bored with your protein source.

Another strategy to up your daily protein intake is to consume a source of protein at every meal.

Having a source of protein at each meal will make sure you are consuming enough protein across the day. Adding protein to a well-balanced meal with some healthy fats, carbohydrates and lots of veggies will also help you stay satiated and full.

To help grow muscle (known as muscle protein synthesis) it is also important to space protein across the day [1]. You can read more on this in our blog article on How to Build Muscle On A Vegan Diet

You might use a protein supplement when:

1. You are unable to consume enough protein from whole foods.

This might be for a number of reasons, including that you have an allergy or intolerance as discussed above. You might also have increased protein requirements because you are trying to gain weight or because you are an athlete. You might just plain not enjoy plant-based protein sources – which brings me to the next reason we might choose to supplement protein.

2. You prefer the taste

I don’t know about you, but I personally am not a fan of savoury breakfasts (no offence if you are – you do you!). So if you’re like me and prefer to have a sweeter tasting breakfast, this is where protein powders can really come in handy to get a decent protein hit in the AM. Protein powders can be added to anything – smoothies, oats, as an extra to yoghurt or even just on its own with water or a milk alternative. Adding protein powder is not detrimental to flavours and can actually make your meal even tastier (hello flavoured protein powder in a smoothie!). Try adding some nuts too for some (extra) protein, as well as some healthy fats!

There are no hard rules on how to eat protein. Whether you supplement or not, the main thing is that you are consuming enough of it and spreading it across your day as best you can! If you aren’t sure if you’re eating enough – speak to your dietitian!

Looking for more tips on how eat more plant based protein? Check our our blog on 6 Top Tips for Transitioning to a Vegan Diet

This blog was co-written by PNW Clinic founder Kiah Paetz and student dietitian by Donna Harris. You can connect with Donna on instagram @pepperandcorndietetics.

If you’re wanting to take your diet to the next level, and book in to see one of our expert dietitians.