If you are looking at the nutrients you need to build up your bones and keep them strong, zinc is near the top of the list.
Zinc is also an essential mineral, meaning you need it just to stay alive. It is used in hundreds of chemical reactions throughout your body.
People I work often show signs of being low in zinc. Zinc can be the missing link that is preventing you from getting the best results from your program to build up your bones.
Table of Contents
Why do we care about zinc?
Every organ and tissue in your body contains zinc. Over 300 enzymes need zinc in order to work. Zinc plays a part in hundreds of biochemical reactions. Here are some of the ways your body uses zinc.
Acid-Base Balance
Zinc helps to keep your body at a normal pH. It is part of an enzyme called carbonic anhydrase, which allows you to get rid of carbon dioxide in your blood (1).
👉🏼 Why this is important for bones…
Your blood likes to stay at a slightly alkaline pH. When it goes out of range there are several body processes that can pull it back. One of them is removing minerals from your bones to buffer your blood. Staying a normal pH range is protective for your bones.
Metabolizing Alcohol
The main enzyme that metabolizes alcohol is called alcohol dehydrogenase. There are four zinc atoms in the structure of this enzyme (2).
👉🏼 Why this is important for bones
If you metabolize alcohol more efficiently it is less of a strain on your liver. Your liver controls inflammation, glucose regulation and bile acid production. All of these are related to bone health.
Producing Stomach Acid
You produce stomach acid through a process which brings hydrogen and chloride ions together to make hydrochloric acid. One important enzyme in this process is carbonic anhydrase.
This is the same enzyme used in acid-base balance, and it needs zinc in order to function efficiently (3).
👉🏼 Why this is important for bones
You need adequate stomach acid in order to digest protein and certain minerals, which of course are important nutrients for your bones.
Digesting Protein
Carboxypeptidases are enzymes that are released from your pancreas to digest proteins in your small intestine. Zinc is required to make these enzymes, and is essential for them to function. So you need zinc to digest proteins efficiently (4).
👉🏼 Why this is important for bones
This is another way zinc helps you get those proteins into your bloodstream where they can build up bone and muscle.
Converting Vitamin A to Active Form
Zinc is necessary to convert retinol to retinal in your body. Retinal is the active form of vitamin A (5).
👉🏼 Why this is important for bones
Bone remodeling is a tightly regulated dance involving many different proteins, which create positive and negative feedback loops. Vitamin A can turn these proteins on and off through its effects on gene expression.
Synthesizing Red Blood Cells
Zinc is an essential player in the production of red blood cells. You need zinc to make the heme part of hemoglobin.
A multi-country analysis showed that zinc is associated with anemia regardless of whether or not there is also an iron deficiency (6).
👉🏼 Why this is important for bones
Hemoglobin supplies oxygen to your bone tissues. The iron in hemoglobin is used in the production of collagen in your bones. Low hemoglobin levels are associated with reduced bone mineral density and increased fracture risk.
Producing Powerful Antioxidants
Superoxide dismutase is an antioxidant found inside your cells, as well as in your plasma, lymph, synovial fluid and lungs. This compound destroys dangerous superoxide radicals that are naturally formed during metabolism.
Zinc is part of the structure of each superoxide dismutase molecule (5).
👉🏼 Why this is important for bones
Oxidative stress creates inflammation, which activates osteoclasts and throws your bone remodeling process off balance.
Digesting B Vitamins
The enzyme that digests vitamin B9, or folate, is called pteroyl glutamate hydrolase. Pteroyl glutamate hydrolase depends on zinc to function properly (5).
👉🏼 Why this is important for bones
Low levels of folate can increase homocysteine in your blood. When homocysteine levels rise it increases the activity of osteoclasts that break down bone (7).
Repairing Wounds
Zinc is part of the structure of a group of enzymes called matrix metalloproteinases. These enzymes are on the front lines of wound healing. They break down damaged tissue and allow new tissue to grow (8).
👉🏼 Why this is important for bones
Matrix metalloproteinases (MMPs) play an important role in the regeneration and remodeling of your bones (9).
Proper Gene Expression
Zinc acts as a stabilizing factor in the processes that promote or inhibit gene expression (5).
👉🏼 Why this is important for bones
Gene expression is important for bone health. You want the right genes to be turned on and off to keep the two parts of the remodeling process—breaking down and repairing bone tissue—balanced.
Metabolism and Immune Function
Zinc influences carbohydrate metabolism and insulin production, supports your immune system, and helps to prevent eye disease like macular degeneration (5).
👉🏼 Why this is important for bones
High blood sugar is inflammatory and can negatively affect your bone health. A weak immune system and inflammation in general can activate osteoclasts and mess up the balance of bone regeneration. Zinc helps to regulate mineralization and stimulate protein synthesis in your bones.
How much zinc do you need?
As with most nutrients, the amount of zinc you need depends on your age and sex. However most female adults who are not pregnant or breastfeeding need about 8 mg of zinc to prevent a deficiency. Males need a slightly larger amount – 11 mg.
How can you get zinc from food?
Animal products provide zinc in a form that is easiest to absorb. Here are some animal-based foods that are high in zinc:
- Oysters are by far the best source, with over 10 mg of zinc per ounce
- 3 oz beef liver – 4 mg zinc
- 3 oz crabmeat – 3.8 mg zinc
- 3 oz ground beef – 3.8 mg zinc
- 3 oz dark chicken meat (ie: thighs) – 2.4 mg zinc
- 3 oz pork – 1.8 mg zinc
- 8 oz yogurt – 1.7 mg zinc
Here are some plant-based foods that are good sources of zinc:
- Whole grains, especially whole wheat
- Pumpkin seeds
- Sunflower seeds
- Cashews
- Peanuts and peanut butter
- Sprouted, cooked lentils
- Soy products
- Winged beans
- Shiitake mushrooms
It’s a little harder to absorb the zinc in plant-based foods because substances like phytates and oxalates can run interference. However you can prepare the foods in ways that lower those substances.
Read this post to learn more about absorbing zinc from plants, and a more comprehensive list of the plant-based foods that contain zinc.
What are the symptoms of zinc deficiency?
The symptoms of zinc deficiency are different for a child and an adult. Children who are not getting enough zinc can have slower growth, abnormal bone development, slow healing of wounds, diarrhea and rashes (10).
Adults who are already physically mature will have a different set of symptoms. Here are a list of possible symptoms you might experience if you have zinc deficiency:
- frequent white spots appear on nails
- symptoms of low stomach acid
- cracks and split skin on fingertips
- weak, bendy or brittle nails
- slow wound healing
- loss of taste and/or smell
- hair loss
- persistent ringing or buzzing in ears
- dry, scaly skin, acne, other skin changes
- thin, fine hair that is easily plucked, hair loss
- diarrhea
Who is at risk for zinc deficiency?
Vegetarians and vegans are at risk for zinc deficiency. This is because the easiest way for your body to digest and absorb zinc is from meat. If you don’t eat meat, you must be more intentional about eating good sources of zinc.
People who drink a lot of alcohol are also at risk for zinc deficiency, since alcohol reduces the absorption of zinc. If you are a vegan and also drink a lot of alcohol, you are increasing your chances of a zinc deficiency.
People with conditions that create malabsorption, such as celiac disease, Crohn’s, prolonged diarrhea, or even bariatric surgery, can be low in zinc.
If you don’t have adequate stomach acid, you could be low in zinc, because you need stomach acid to absorb zinc. (You may have noticed you also need zinc to make stomach acid.)
How to Assess Your Zinc Status With Labs
Plasma and serum, which you would get from a normal blood draw, are not a great way to check zinc status. That’s because only a very small portion of your body’s zinc is in your bloodstream. Most of it is inside your cells.
A better way to measure is with erythrocyte, or red blood cell zinc (RBC). Red blood cells contain many enzymes with zinc in their structure, so there is a lot more present than in the bloodstream. They can also tell you about zinc stores for the past 3-4 months, which is the lifespan of a red blood cell.
Another way to assess your zinc levels is with RBC metallothionein (MT), a molecule that transports zinc and can decrease when zinc is depleted.
Low levels of alkaline phosphatase (ALP) can be an indicator of low zinc. However many other things can also affect ALP, so you would not make a judgement just based on this one marker. It is something you could look at along with symptoms, how much zinc you are eating, and other labs.
Final Thoughts
Every organ system in your body needs zinc to function properly. Zinc is involved in hundreds of processes that keep your bones and other body systems healthy.
It’s easy to get zinc if you are intentional about eating the meats, seafood and / or plant-based foods that are good sources of this mineral.
However, if you have malabsorption disorders, drink a lot of alcohol, have low stomach acid, or don’t eat any animal products, you might be low on zinc. You can assess your zinc levels with labs and some physical signs and symptoms.
What are your favorite ways to get zinc? Let me know in the comments.