This lesson will introduce you to ways of supporting the endocrine system within the context of a range of endocrine disorders. Each section covers dietary and lifestyle considerations as well as supporting herbs. The aim of the lesson is to give you a broad understanding which you can then integrate into a larger wellness strategy for your client. Throughout this unit you should consider the interconnectedness of different endocrine disorders and the nervous system discussed in Lesson 2 of this unit. This lesson also links with Lesson 4 in which you will learn about different endocrine disorders in more detail. Throughout all of these lessons, and in clinical practice, it is important to develop your critical thinking skills and to support people holistically.
Supporting the nervous system is at the heart of supporting a number of hypothalamic-pituitary disorders. Not only does sustained stress disrupt the hypothalamic-pituitary-adrenal (HPA) axis, but it also impacts the other hypothalamic-pituitary axes (such as the thyroid and growth hormone axes) (Considine, 2013; Pocock & Richards, 2006). Furthermore, as discussed in Lesson 2 of this unit, stress activates the sympathetic nervous system, causing the adrenal glands to release epinephrine, norepinephrine, and glucocorticoids. These are all glucogenic hormones which raise blood glucose levels (Pocock & Richards, 2006).
Relaxation exercises – such as diaphragmatic breathing, visualization, yoga, and meditation – enable a switch from the stress response (in which the sympathetic nervous system dominates) to the relaxation response (in which the parasympathetic nervous system dominates) (Bove et al., 2010; Murray, 2014a).
Exploring hobbies and interests also reduces stress; for example someone who loves art could be encouraged to take up drawing and painting or to join a local art class. Being surrounded by nature (i.e. through walking or gardening) is particularly beneficial. Studies have shown that being in nature (rather than urban environments) helps people to recover from stress more quickly, and that both the sights and sounds of nature have positive effects (Alvarsson et al., 2010; Parsons et al., 1998; Ulrich et al., 1991). Research has also shown that when patients in hospitals are exposed to plants in their rooms they experienced shorter stays, lower heart rate and systolic blood pressure, less pain, need fewer analgesics, and were less anxious and fatigued than those with no plants in their room (Park, 2006; Park & Mattson, 2008). Itis also important that people have adequate social support; those without have reduced life expectancy (Berkman et al., 1992; Rosengren et al., 1993; Rutledge et al., 2004).
Poor sleep affects physical and mental function. Disruption of diurnal sleep patterns (sleeping at night and being awake during the day) can affect hormone secretion – for example, corticosteroid secretion follows a circadian rhythm (Considine, 2013). Establishing good sleep hygiene can be helpful where there are sleep problems – for example, waking up at the same time every day to ensure a sleep-wake rhythm, avoiding caffeine in the evening, ensuring that the bedroom is cool and dark and most importantly a place for sleeping, and relaxing in the evening (Hoffmann, 2003; Murray, 2012). Drinking alcohol affects serotonin levels and releases adrenaline, and can thus affect sleep (Murray, 2012). Regular daily exercise can help to promote sleep providing it is not just before bedtime (Hoffmann, 2003). Ensuring good blood sugar regulation (discussed in depth later) also promotes sleep; a drop in blood sugar levels during the night can cause the person to wake (maintenance insomnia) (Pizzorno et al., 2008).
The adrenal glands need vitamin B5 (Pantothenic acid), vitamin C and folic acid to function properly (Haas, 1992). Meats, vegetables, and cereals are the main sources of vitamin B5. Green leafy vegetables such as chard, spinach, and kale are the best sources of folic acid. Citrus fruits are very high in vitamin C (Barasi, 2003).
Excessive consumption of caffeine can cause symptoms including nervousness, palpitations, insomnia, depression, mood changes, and headaches. Some people, particularly those who are anxious and stressed, are more sensitive to caffeine than others (Murray, 2014a). Furthermore, caffeine causes depletion of B vitamins (Hechtman, 2012).
Exercise increases the production of endorphins which elevate the mood. Exercise also decreases anxiety and malaise, promotes happiness, and can reduce depression (Pizzorno et al., 2008).
Research investigating the gut-brain axis has focused on the impact that the brain has on the gut, for example the impact of stress on functional bowel disorders, such as irritable bowel syndrome (Neufeld & Foster, 2009). Emerging research indicates that the gut-brain axis is bidirectional. For example, a study by Tillisch et al. (2013) investigated the effects of a fermented milk product containing the probiotics Bifidobacterium animalis subsp Lactis, Streptococcus thermophiles, Lactobacillus bulgaricus, and Lactococcus lactis subsp. Lactis in 36 healthy women. The study found that the fermented milk product modulated brain activity, affecting regions of the brain that control the central processing of emotion. A study by Messaoudi et al. (2010) investigated the psychotropic effects on humans of a probiotic formulation containing Lactobacillus helveticus R0052 and Bifidobacterium longum R0175 (PF). Fifty-five healthy participants, exposed to everyday life events, completed the 30-day randomised, double-blind, placebo-controlled, parallel clinical study. The study found that those receiving the probiotic formulation showed beneficial effects in relation to signs of anxiety and depression, and lowered urinary cortisol levels.
A study by Schmidt et al. (2014) investigated the effects of taking prebiotics Bimuno®-galactooligosaccharides (B-GOS) and fructooligosaccharides (FOS) on 45 healthy volunteers. After 3 weeks those who took the B-GOS had lower salivary cortisol levels on waking, and paid more attention to positive words and less attention to negative words compared to placebo (thus B-GOS affected their emotional processing), whereas those who took the prebiotic FOS showed no change to cortisol levels or emotional processing. Animal studies by Savignac et al. (2013) have also indicated that GOS increases proliferation of gut microbiota more than FOS; this may explain why Schmidt et al. (2014) found B-GOS to be more effective than FOS. Schmidt et al. (2014) propose that prebiotics may modulate the HPA axis, and that the positive impact of B-GOS on emotional processing is comparable with the effects of citalopram and diazepam on healthy volunteers.
Although the effects of both prebiotics and probiotics on anxiety and depression warrant further research, the findings so far suggest that promoting healthy gut bacteria should be considered when supporting people with anxiety.
Adaptogens play an important role in increasing the body’s resistance to the negative effects of stress. They help to adapt to stress by supporting the neuroendocrine system and their amphoteric effects help to maintain homeostasis (Winston & Maimes, 2007). Adaptogens normalize the HPA axis by supporting the adrenal glands to both respond to stress and to stop releasing stress hormones when the stressful situation is over. Furthermore, by increasing the sensitivity of the hypothalamic receptors the adrenal glands can release lower levels of stress hormones to achieve the same response (Yance, 2013). Adaptogens that specifically support the adrenal glands include ashwagandha (Withania somnifera), eleuthero (Eleutherococcus senticosus), licorice (Glycyrrhiza glabra), American ginseng (Panax quinquefolius) (for mild to moderate HPA depletion), rhodiola (Rhodiola rosea) and schizandra (Schizandra sinensis). Schizandra, ashwagandha, Asian ginseng, and rhodiola also help to relieve anxiety and depression (Winston & Maimes, 2007).
Nervines can be used alongside adaptogens to complement their effects on the nervous system. Some adaptogens, such as ashwagandha, schizandra, eleuthero, and rhodiola are also nervines (Winston & Maimes, 2007). Nerve tonics and relaxing nervines are indicated for supporting anxiety and stress.
Nerve tonics strengthen and feed the nervous system (Hoffmann, 1997). Milky oats (Avena sativa), skullcap (Scutellaria laterifolia), damiana (Turnera diffusa), St. John’s wort (Hypericum perforatum), vervain (Verbena officinalis) and wood betony (Stachys betonica) are examples of nerve tonics (Bartram, 1998; Hoffmann, 1997). Relaxing nervines can be used to ease anxiety and tension; examples include linden (Tilia spp.), passionflower (Passiflora incarnata), lavender (Lavendula angustifolia), valerian (Valeriana officinalis), and motherwort (Leonurus cardiaca). St. John’s wort and lemon balm (Melissa officinalis) are nervines which have an uplifting and anti-depressant effect (Hoffmann, 1997; Winston & Maimes, 2007).
Goitrogens can block the synthesis of thyroid hormones by inhibiting the uptake of iodine, interfere with the organification of iodide, or affect the release of thyroid hormones (Gropper & Smith, 2012). A number of foods, pharmaceutical drugs and environmental pollutants have been identified as being goitrogenic (see Table 1). Furthermore, some pharmaceuticals (carbamazepine, phenytoin, phenobarbitone, and rifampin) also cause metabolic degraduation of T4 and T3. Amiodarone and propylthiouracil inhibit the conversion of T4 to the more potent T3 (Tripathi, 2013).
Table 1: Examples of Goitrogenic Substances | ||
Source | Examples | Notes |
Foods | Cruciferous vegetables (Brassica family), i.e. cabbage, kale, turnips, broccoli and rapeseed – contain glucosinolates. Metabolites of glucosinolates compete with iodine (Zimmermann, 2012) | Cooking/heating these foods renders them inactive (Murray & Pizzorno, 1990a) |
Lima beans, cassava, sweet potato and linseed contain cyanogenic glucosides which may be metabolized to thiocynates (Zimmermann, 2012). Cassava contains the cyanogenic glucoside linaramin which is converted to thiocyanate (which competes with iodine for thyroidal uptake) (Gropper & Smith, 2012; Zimmermann, 2012) | Soaking and cooking cassava removes the linaramin (Zimmermann, 2012). | |
Soy and millet – may be goitrogenic (Zimmermann, 2012). | ||
Medications | Lithium inhibits the release of thyroid hormones; thionamides including methimazole, carbomazole and propylthiouracil (antithyroid medication), aminoglutethimide (an antiadrenal medication which inhibits iodide organification), carbutimide, amiodarane (an antiarrhythmic medication – effect is mainly due to iodine content) (Davis & Davis, 2001; Tripathi, 2013; Zimmermann, 2012). | |
Environmental |
Some humic substances (components of organic matter) in drinking water are goitrogenic. Geology and geochemistry affects the concentration and characteristics of humic substances (Anderson & Laurberg, 2009). | Both humic substances and iodine are found in drinking water (Anderson & Laurberg, 2009). |
Perchlorate (a drinking water contaminant) (Gropper & Smith, 2012). |
Stress disrupts the hypothalamic-pituitary-thyroid (HPT) axis, reducing the production of thyroid hormones. Furthermore, the peripheral conversion of the inactive T4 to the active T3 can be inhibited by glucocorticoids (Andrews et al., 2015). Stress can also cause immune dysregulation and thus autoimmune conditions (Bone, 1994; Mizokami et al., 2004); it is known to trigger Grave’s disease (Longmore et al., 2014; Murray & Pizzorno, 1999a) and possibly Hashimoto’s thyroiditis. However, given the insidious nature of the latter, this is harder to establish. Stress reduction techniques, such as those discussed earlier in this lesson, can be effective in supporting thyroid health.
As well as helping to maintain a healthy weight, exercise stimulates the thyroid to secrete thyroid hormones and increases the sensitivity of tissues to thyroid hormones (Pizzorno et al., 2008).
Zinc and vitamins A, E, B2 (riboflavin), B3 (niacin), and B6 (pyridoxine) are all needed for the synthesis of thyroid hormones (Murray & Pizzorno, 1999a). Sources of zinc include oysters, yeast, eggs, beef, herring, seeds, fruit, nuts, peas, shellfish, and poultry. Sources of vitamin A include fish oils, liver, organic milk, and egg yolks. Yellow and orange colored fruit and vegetables are a good source of carotenoids (provitamin A), which are converted to retinol (a form of vitamin A) (Barasi, 2003; Haas, 1992). To maintain a healthy thyroid, adequate but not excessive amounts of vitamin A should be taken as large amounts can inhibit thyroid function (Pizzorno et al., 2008). Furthermore, toxicity can occur through excessive consumption (usually occurring through supplementing, though it can occur through excessive consumption of liver) (Haas, 1992). Eggs, meat and brewer’s yeast are good sources of vitamins B2, B5, and B6 (McIntyre, 1999).
Selenium, zinc, and copper are required for the conversion of T4 to T3 (Pizzorno et al., 2008). Brazil nuts, garlic, brewer’s yeast, and whole grains contain selenium. Organ meats (i.e. liver), green leafy vegetables, whole grains, eggs, beans, nuts, and seafood are sources of copper (McIntyre, 1999; Pizzorno et al., 2008). In hyperthyroidism, antioxidants such as vitamin C and E are also needed to protect from oxidative damage (caused by elevated thyroid hormones). Furthermore, hyperthyroidism affects calcium metabolism, increasing the risk of osteoporosis (Pizzorno et al., 2008).
Ensuring an adequate – but not excessive – intake of iodine is important as it is needed for thyroid hormone synthesis. The recommended daily allowance of iodine for adults is 150 μg/day (Whitney & Rolfes, 2013). According to Nussey & Whitehead (2001) the thyroid uses 125 μg/day for thyroid hormone synthesis. In chronic states of iodine deficiency the thyroid gland enlarges in an attempt to accumulate more iodine from the blood and thus increases the synthesis of T3 and T4 (Andrews et al., 2015). Iodine deficiency is rare in the United States and Canada (due to iodized salt), though is the most common form of iodine deficiency worldwide (Axford & O’Callaghan, 2004; Vanderpump, 2011). It is worth noting that too much iodine can inhibit the synthesis of thyroid hormones, and thus exacerbate hypothyroidism (Murray & Pizzorno, 1999a) – given this, supplements should be avoided unless iodine deficiency is the cause. Sources of iodine include sea vegetables (such as kelp), sea fish, and iodized salt (Murray & Pizzorno, 1999a).
There is a distinct lack of research investigating the use of herbs for hypothyroidism (Bove et al., 2010). According to Winston and Maimes (2007), rhodiola, ashwagandha and holy basil (Ocimum sanctum) are indicated for hypothyroidism. Rhodiola supports thyroid function but does not cause hyperthyroidism. As adaptogens, they have the additional benefit of helping to regulate the hypothalamic axis and reduce oxidative stress (seen in both hypo- and hyperthyroidism) (Bove et al., 2010). Ashwagandha has been shown to have thyroid-stimulating activity in mice (Panda & Kar, 1998; 1999). However, there is a distinct lack of research investigating the effects in humans. Coleus (Coleus forkohlii) and guggul (Commiphora mukul) are also indicated for hypothyroidism (Bone & Mills, 2013).
There are a number of herbs which are considered to have anti-thyroid activity, for example bugleweed (Lycopus virginicus/europaeus), lemon balm, motherwort and gromwell (Lithospermum officinale) (Bove et al., 2010).
Modern herbalists use motherwort to support people with hyperthyroidism (Bartram, 1998; Bove et al., 2010; Hoffmann, 2003). It is a cardiotonic which is particularly indicated for palpitations and rapid heartbeat associated with anxiety and hyperthyroidism (Chevallier, 2008; Hoffmann, 1997; McIntyre, 1999). A lack of research investigating the effect of motherwort on thyroid function makes it hard to determine whether it only offers symptomatic relief, or whether it has also has anti-thyroid activity as well.
According to Mills & Bone (2008), lemon balm is a TSH antagonist. Although they do not advocate that it should be avoided/used cautiously in hypothyroidism, a number of other authors do (Braun & Cohen, 2015; Hoffmann, 2003; Winston & Maimes, 2007). Lemon balm is an uplifting nervine, beneficial for when depression or anxiety affects the heart and causes symptoms such as palpitations (McIntyre, 1999), thus offering relief for some of the symptoms of hyperthyroidism. In vitro research suggests that lemon balm has anti-thyroid properties (Auf’mkolk et al., 1984; Auf’mkolk et al., 1985), However, extrapolating the results from this in vitro research to effects in living human beings is impossible. To date there are no studies investigating the effects of lemon balm on thyroid levels in humans, therefore further research in this area is needed before making claims about its effect on the thyroid. However, given its nervine action, using lemon balm in conjunction with bugleweed is recommended.
Insulin resistance can not only lead to type 2 diabetes mellitus and metabolic syndrome, it is seen in polycystic ovary syndrome (PCOS) and has been linked to other diseases such as Alzheimer’s disease, some cancers, and non-alcoholic steatorrhea hepatitis (NASH) (Bone & Mills, 2013). In the case of PCOS, insulin resistance is estimated to affect around 50-70% of women with the condition. Raised levels of circulating insulin increase the production of androgens (Trickey, 2003). Thus regulating blood sugar levels can play a significant role in both the prevention and support of PCOS (this condition will be discussed in greater depth in Unit 7: Female Health and Wellness). Good blood sugar control significantly reduces the likelihood of complications of hyperglycaemia (Murray & Pizzorno, 1999b). Attention should also be given to minimizing factors that disrupt the body’s ability to maintain blood sugar homeostasis, such as elevated cortisol levels. We will be having more in-depth discussions on sugar metabolism in the following lesson, as well as in Unit 10: Weight Management for Health and Wellness.
To help maintain blood sugar regulation, sugars should be consumed in limited amounts as they cause a rapid increase in blood sugar levels and thus elevated insulin levels (Murray, 2014b). Blood sugar spikes compromise the homeostatic mechanisms which regulate blood sugar levels. An ecologic analysis by Gross et al. (2004) found that type 2 diabetes mellitus was strongly associated with an increased consumption of refined carbohydrates and a low consumption of dietary fiber. Foods with a low glycemic index (GI) (e.g., oats, lentils and beans) are broken down more slowly than those with a high GI (e.g., white bread) – thus they raise blood sugar levels more slowly and consequently less insulin is released (Thomas & Elliott, 2009). Many alternatives to refined carbohydrates and sugar, especially within the context of weight management, will be discussed in further detail in Unit 10: Weight Management for Health and Wellness.
Eating a diet high in fiber improves insulin sensitivity (Weickert & Pfeiffer, 2008). Good sources of water-soluble fiber are legumes, oat bran, nuts, seeds, psyllium seed husks, pears, apples, and most vegetables (Pizzorno et al., 2008).
Regular exercise improves insulin sensitivity and helps maintain a healthy body weight (Bone & Mills, 2013). For people who are overweight, sensible weight loss reduces insulin resistance (Hechtman, 2012). We will be discussing weight management for health and wellness in Unit 10.
Raised adrenaline and cortisol levels increase blood glucose levels and insulin resistance (Hechtman, 2012), thus stress management techniques are beneficial for helping to maintain blood sugar regulation and for those with diabetes mellitus (by reducing the impact of stress on blood sugar regulation). Furthermore, those with diabetes are more prone to depression (both before and after onset) and can find living with diabetes challenging (Banasik, 2013). Stress reduction techniques, such as those discussed earlier in this lesson, can be helpful. Obtaining adequate sleep is important for regulating blood sugar levels (Pizzorno et al., 2008).
Epidemiological studies show that low dietary intake of magnesium increases the risk of developing type 2 diabetes (Emoto & Nishizawa, 2007). Studies have also shown that magnesium increases insulin sensitivity in people with type 2 diabetes (Stargrove et al., 2008). Stargrove et al. (2008) recommend a dose of 200-600 mg of elemental magnesium per day for diabetics. It is recommended that magnesium status and kidney function are assessed prior to supplementing. Furthermore, insulin levels need to be regularly monitored. Dietary sources of magnesium include brewer’s yeast, buckwheat, wheat bran, and nuts (cashews, brazil nuts, and almonds). Magnesium deficiency can result from taking a number of pharmaceutical drugs, in particular furosemide, aminoglycosides, and amphotericin-B (Stargrove et al., 2008).
Chromium is important for ensuring blood glucose homeostasis – it activates insulin receptor kinase, increases insulin sensitivity and binding, increases insulin receptor numbers, and promotes glucose uptake. In addition, chromium may lower low-density (LDL) and raise high-density (HDL) cholesterol levels (Stargrove et al., 2008). Dietary sources of chromium include Brewer’s yeast, liver, beef, whole grains, molasses, and wheat germ (Haas, 1992; McIntyre, 1999). However, chromium is difficult to absorb (this worsens with age) and low levels of chromium in modern day soils increase the likelihood of deficiency. Furthermore, refined foods, high in sugars and fats, often contain low levels of chromium (Haas, 1992).
Those who are diabetic and/or insulin resistant can supplement with antioxidants (i.e. vitamin E) to improve insulin sensitivity (Trickey, 2003). Dietary sources of vitamin E include cold-pressed oils (particularly wheat germ oil), nuts, grains, and sprouted seeds (Stargrove et al., 2008).
A number of herbs are indicated for regulating blood sugar levels. These include goat’s rue (Galega officinalis), gymnema (Gymnema sylvestre), and fenugreek (Trigonella foenum-graecum) (Mills & Bone, 2008). We will be revisiting some of these herbs in Unit 10: Weight Management for Health and Wellness. Adaptogens are beneficial for helping the body to cope with and respond to stress, and are therefore indicated for assisting in blood sugar regulation. Key adaptogens which help to regulate blood sugar levels include holy basil, eleuthero, and American ginseng (Panax quinquefolius). Clinical studies support the use of holy basil for reducing blood sugar levels in people with type 2 diabetes mellitus (Winston & Maimes, 2007). Shishtar et al. (2014) conducted a systematic review and meta-analysis of randomized-controlled trials investigating the effect of ginseng (Panax spp.) on glycemic control. 16 studies met the inclusion criteria (12 of these investigated Panax ginseng, 3 investigated American ginseng and 1 was unspecified). The review found that Panax spp. significantly improved fasting blood glucose levels in those with diabetes (and to a lesser degree in those without diabetes). However, larger and longer randomized controlled trials are needed to substantiate these findings.
Reducing stress (physiological and psychological), eating a balanced and varied diet rich in whole foods, obtaining adequate sleep, reducing stimulants, and partaking in regular exercise are important for the endocrine system. When supporting people whose endocrine system is out of balance, it is vital to think holistically about what could have contributed to the development of the condition. It is also important to make recommendations that are achievable. Educating your client about dietary and lifestyle factors in a non-judgmental manner can help them to see the importance of making changes and thus increase adherence.
Adaptogens: Herbs for Strength, Stamina, and Stress Relief by David Winston and Steven Maimes
Adaptogens in Medical Herbalism by Donald Yance
The Clinician’s Handbook of Natural Medicine by Joseph Pizzorno, Michael Murray and Herb Joiner-Bey
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