Bone Health and Gut Inflammation – What's The Connection?
By Christine Lewis
Managing the health of your bones is another essential aspect to consider for those with inflammatory gut conditions.
According to Coeliac UK, intestinal damage seen in untreated coeliac disease can lead to chronic malabsorption of nutrients, including calcium. Calcium malabsorption and subnormal levels of serum calcium result in damage to bone health.
Also, osteoporosis is a known complication of Irritable Bowel Diseases (IBD), such as Crohn's disease and ulcerative colitis (Miznerova, 2020).
Although Irritable Bowel Syndrome (IBS) is not currently considered a risk factor for osteoporosis, a recent large-scale review of scientific data – a meta-analysis, concluded there was a significantly increased risk of osteoporosis among IBS patients from the study data (Wongtrkul, 2020).
Let's look at how bones form
It might not appear like a living organ, but bone is constantly being built up and broken down through a process called bone re-modelling. Cells that build our bones are called osteoblasts, and cells that break down bone are known as osteoclasts. It's essential for good bone health that these two types of cells are in balance.
When this delicate balance of cells becomes unbalanced over a period of time, osteoporosis can start to develop. You may have heard of osteopenia; this is the forerunner of osteoporosis. Osteoporosis is a silent condition which can lead to fragility fractures, especially of the hips.
Bone re-modelling can be influenced by several factors such as fluctuations in hormone levels, nutrient deficiencies, and environmental factors. We will look at these in more detail further on.
What triggers osteoporosis?
What is now known is that the process of long-term chronic inflammation disrupts the balance between osteoblast and osteoclast cell formation, creating an environment where osteoclasts dominate. This imbalance, over time, causes a decrease in bone density. In fact, scientists have coined the term "immunoporosis" to emphasise the role of immune cells in the development of osteoporosis (Saxena, 2021).
What causes inflammation?
Inflammatory gut conditions, by their very nature, are often accompanied by an inflamed gastric environment which causes the release of immune defensive cells throughout the body that have the effect of preventing bone re-modelling. It seems that when the body has more urgent things to prioritise, such as inflammation, it appears to redivert resources away from general maintenance. This may be a protective mechanism due to the need to preserve our stock of nutrients used at a faster rate in response to inflammatory reactions. Keeping the diet free of trigger foods and known inflammatory causing foods such as gluten and dairy for those with reactive food conditions is essential. There is a lot more you can do to mitigate the disadvantages of having this type of risk factor by being aware of and avoiding other inflammatory causing habits or conditions.
Some causes of inflammation which can be directly linked to abnormalities of bone density are lifestyle choices such as smoking or drinking alcohol regularly and need to be avoided where other known inflammatory risks exist.
Reductions in the level of oestrogen in a woman during menopause are one of the most understood links to increased inflammation and a corresponding drop in bone density. This, of course, is unavoidable for women. Still, dietary adjustments can help support bone health through sufficient protein intake and gaining essential bone health micronutrients from within the diet. Bone formation only occurs in an anabolic state, and this means that when your diet doesn't contain sufficient calories or protein and where body mass is very low, bone re-modelling or bone regeneration will not happen.
Lowering your intake of sugar and refined carbohydrates will reduce the known inflammatory response caused when we create too much insulin over long periods of time. A review of the studies into the overconsumption of dietary sugar shows the potential to increase the risk of osteoporosis by its inflammatory nature. As well as increasing inflammation, this report found that sugar increases our acid load and increases calcium excretion (Di Nicolantonio, 2018).
Other risk factors of low bone density
Having a small frame is also considered a risk factor, as are the autoimmune conditions; coeliac disease, IBD – Crohn's, type 1 diabetes, and rheumatoid arthritis. Several medications, according to the Royal Osteoporosis Society, affect bone density, such as steroids and epilepsy medications. Proton Pump inhibitors (PPIs), injectable progestogen contraceptives, and medicines used for mental health conditions, such as tricyclic antidepressants and selective serotonin reuptake inhibitors (SSRIs), may also affect bone health.
An interesting new area of research is looking at the role the gut microbiome plays in regulating bone density.
The new gut bone science and what it means
The relationship between our gut microbiome and our health is a growing area of research which it seems also has implications for bone health. A number of research findings show that low bone density and osteoporosis is related to changes in the gut microbiome compared to healthy samples. Also, having prior exposure to more inflammatory types of gut bacteria represents a future higher risk for osteoporosis. The use of prebiotics and mixed strain probiotics have been found to increase the production of Short Chain Fatty Acids such as Butyrate, which helps to repair the lining of the gut. In a study (Jia, 2021), oestrogen deprivation-induced inflammatory responses were suppressed using mixed strain probiotics over a three-month period.
Key nutrients for bone health and some simple tips
Nutritional aspects of bone health are always considered among the main factors capable of triggering bone alterations, especially regarding the intake of calcium and vitamin D, the lack of which, both in adults and children, shows a direct correlation with the increased probability of developing bone fragility.
Approximately 50% of bone volume and about a third of bone mass is composed of proteins. Studies have found that low protein intake decreases calcium absorption and may also affect rates of bone formation and breakdown (Munoz-Garach, 2020).
It is worth mentioning here that getting a good balance of protein and vegetables is also needed. Researchers have concluded that too much protein, which is a typical feature of the average western diet which is high in protein and low in vegetables and fruits, can have a negative effect on calcium absorption into bones (Barzel, 1998).
The recommended daily intake of protein is .83g of protein per kilogram of weight for the average person.
If you have lactose intolerance or are following a vegan diet, you need to be particularly careful you combine foods to give sufficient daily calcium intake. The recommended daily intake of calcium is 1,000mg each day. Calcium absorbs better if it is taken frequently throughout the day rather than in one large single food serving. Plan to incorporate some calcium-containing food in each meal and snack by using the following guidelines.
Foods providing around 50mg of calcium per average portion
- Plain yoghurt - 1 tablespoon (40g)
- Green or French beans - 1 serving (90g)
- Green cabbage - 1 serving (95g)
- Raw, white cabbage - 1 serving (90g)
- Steamed broccoli - 1 large portion (110g)
- Watercress - 1 small bag (40g)
- Fried onion - 1 medium-sized (150g)
- Tinned tomatoes - 1 tin (400g)
- Red kidney beans - 2 tbsp (70g)
- Vegetable casserole - 1 serving (260g)
- Veggie burger - 1 (56g)
- Boiled basmati rice - 2 portions (1 portion = 5 heaped tbsp)
- Dried apricots 8 (64g)
- Orange - 1 large orange (50g)
- Easy peel citrus e.g. tangerines/satsumas - 3 medium easy peelers (210g)
- Almonds 10 - whole nuts (22g)
- Brazil nuts - 9 whole nuts (30g)
Foods providing around 100mg of calcium per average portion
- Kale (254g)
- Cottage cheese - 2 tbsp (80g)
- Camembert - 1 portion (1/6 round, 40g)
- Baked beans - 1 small tin (200g)
- Sesame seeds - 1 tbsp (12g)
- Tinned pink salmon - 1 small tin (105g)
- Grilled herring - 1 (119g)
- Dried figs - 2 (40g)
Foods providing around 200mg of calcium per average portion
- Milk or milk drink e.g. hot chocolate (skimmed/semi-skimmed/whole) - 1 tumbler or mug (200ml)
- Cheddar cheese & low fat hard cheese - Small matchbox size (30g)
- Yoghurt (low fat fruit, plain & calcium boosted soya) - 1 pot (125g)
- Porridge (made with semi-skimmed milk) - 1 bowl (160g - weight with milk)
- Halloumi - 1/2 serving (35g)
- Cauliflower cheese - 1 serving (200g)
- Canned sardines - 1 serving for a sandwich (50g)
- Rice pudding - 1 serving (200g)
Foods providing around 300mg of calcium per average portion
- Edam or gouda - 1 portion (40g)
- Parmesan cheese - 1 serving (30g)
- Cheese omelette - 1 serving (120g)
- Quiche cheese and egg - 1 serving (140g)
- Macaroni cheese - 1 serving (220g)
Vitamin D and Vitamin K
Vitamin D is essential for the proper absorption of calcium from the gut. Unfortunately, vitamin D deficiency is very common, affecting about one billion people worldwide. You may be able to get enough vitamin D through sun exposure and food sources such as fatty fish – salmon, herrings, mackerel etc., liver and cheese. However, many people need to supplement with up to 2,000 IU of vitamin D daily to maintain optimal levels.
Vitamin K2 is required for the integration of calcium into bone. Vitamin K2 is found in liver and fermented soya (Natto). Vitamin K2 is often accompanied in vitamin D supplements as they both work together more effectively for bone health.
Vitamin C is an important element of collagen which is used in bone formation. This vitamin is easy to obtain from the diet and is found in bell peppers, broccoli, strawberries, pineapple, organs, and kiwi fruit, as well as many other fruits and vegetables.
Magnesium is a major component of bone. Observational studies have shown that a low intake of magnesium is a risk factor for osteoporosis. Magnesium has many roles within the body, one of which is to activate Vitamin D for absorption into bone. Nutritional monitoring programs have shown an inadequate dietary magnesium intake in Europe (Castiglioni, 2013), mainly due to the features of the western diet, which is rich in processed foods and relatively poor in micronutrients. The green colour seen in many vegetables is from chlorophyll, and this contains a good level of magnesium, so green vegetables are excellent sources of this mineral. Also, nuts, seeds, unprocessed grains, and some legumes contain large amounts of magnesium.
Exercise and Bone Health
Our skeleton is sensitive to gravity, and weight-bearing physical activity is a stimulus to maintain and build bone. Individuals with better muscle strength have stronger bones, fall less, and have fewer fractures. Both vitamin D and exercise have been proven to improve bone health and reduce falls by 50% (Bischoff, 2001).
Facts about exercise and bone health
- Rapid, short bursts of high intensity and/or high impact activities such as jogging, jumping, and rope skipping are more stimulating to bone cells than sustained, low impact activities such as walking.
- Effective activity does not have to be weight-bearing. Resistance training (lifting weights) is an effective non-weight-bearing activity.
- Aerobic activity that is non-weight-bearing (such as swimming or cycling) does not enhance bone density.
- Lifting heavy weights is more effective than lifting light weights.
- Lifting heavy weights rapidly (power training) seems to be more effective than lifting heavy weights slowly (traditional resistance training).
- Rapid movements are more stimulating than slow movements.
- Muscles connected to the bones that are most susceptible to fracture (hip, wrist, thoracic spine) should be targeted with specific exercises.
The facts in this article are not designed to take the place of professional medical guidance. If you feel you have an increased risk factor for osteoporosis, please discuss this with your GP.
Barzel, U. S. (1998) Excess dietary protein can adversely affect bone
Bischoff, H. et al. (2001) Self-reported exercise before age 40: influence on quantitative skeletal ultrasound and fall risk in the elderly.
Castiglioni, S. (2013) Magnesium and Osteoporosis: Current State of Knowledge and Future Research Directions
DiNicolantonio, J. J. (2018) Not Salt But Sugar As Aetiological In Osteoporosis: A Review
Jia, L. et al. (2021) Probiotics ameliorate alveolar bone loss by regulating gut microbiota
Miznerova, E. et al. ( 2020 ) The prevalence and risk factors for osteoporosis in patients with inflammatory bowel disease
Munoz-Garach, A. (2020) Nutrients and Dietary Patterns Related to Osteoporosis
Saxena, Y. (2021) Immunoporosis: Role of Innate Immune Cells in Osteoporosis
Wongtrkul, W. (2020) The association between irritable bowel syndrome and osteoporosis: a systematic review and meta-analysis