High Blood Sugar and Insulin Resistance

Repeated high blood sugar levels can create imbalances leading to insulin resistance. Chronically high levels of blood sugar and insulin can create conditions favorable to cancer growth and spread.

What approaches can help you manage high blood sugar and insulin resistance?

Conventionalthe medical care offered by conventionally trained physicians and most hospitals; examples are insulin and metformin, self-carelifestyle actions and behaviors that may impact cancer outcomes; examples include eating health-promoting foods, limiting alcohol, increasing physical activity, and managing stress, and complementaryin cancer care, complementary care involves the use of therapies intended to enhance or add to standard conventional treatments; examples include supplements, mind-body approaches such as yoga or psychosocial therapy, and acupuncture approaches are all available to help you control high blood sugar or correct insulin resistance. These almost always require monitoring and guidance from a health professional.

Top practices and therapies for managing high blood sugar and insulin resistance

Therapies and practices we have reviewed

Further therapies

Therapies recommended in clinical practice guidelines but that we haven’t yet reviewed; see guidelines ›

Aloe vera (oral)

Alpha-lipoic acid

A specific Ayurveda formulation of six herbs

Citrullus colocynthis

Coccinia cordifolia

Fenugreek (Trigonella foenum graecum)

Ginger

Gynostemma pentaphyllum

Hintonia latiflora

Lichen genus Cladonia BAFS “Yagel-Detox”

Marine collagen peptides

Milk thistle ›

Nettle

Omega-3 fatty acid eicosapentaenoic acid ›

Pterocarpus marsupium (vijayasar)

Salacia reticulata 

Scoparia dulcis porridge

Soybean-derived pinitol extract

Touchi soybean extract

Traditional Chinese medicine herbs:

  • Fructus mume
  • Gegen Qinlian Decoction (GQD)
  • Jianyutangkang (JYTK) with metformin
  • Jinlida with metformin
  • Sancaijiangtang
  • Shen-Qi-Formula (SQF) with insulin
  • Tang-Min-Ling-Wan (TM81)
  • Xiaoke (contains glyburide)
  • Zishentongluo (ZSTL)

Other therapies

Several other therapies have some evidence of benefit for managing high blood sugar and insulin resistance. The benefit may be meaningful or even substantial, but our reviews show the evidence so far is preliminary. These are described below.

Conventional approaches

Many conventional approaches are available to control high blood sugar and diabetes. Your medical team should be able to help you find the best approach for your situation.

Metformin may be a good choice, as substantial evidence shows better survival after cancer diagnosis among people with diabetes treated with metformin compared to other diabetes medications.

Self-care practices and complementary therapies

Practices or therapies with good or modest evidence of benefit

Strong evidenceconsistent, significant effects in several large (or at least one very large) well designed clinical studies or at least two meta-analyses of clinical studies of moderate or better quality (or one large meta-analysis) finding similar results (this is the CancerChoices definition; other researchers and studies may define this differently) indicates confidence that the practice or therapy has an effect as noted. Good evidencesignificant effects in one large or several mid-sized and well-designed clinical studies (randomized controlled trials (RCTs) with an appropriate placebo or other strong comparison control or observational studies that control for confounds) (this is the CancerChoices definition; other researchers and studies may define this differently) indicates that the practice or therapy is linked to the outcomes described with reasonable certainty. Modest evidencesignificant effects in at least three small but well-designed randomized controlled trials (RCTs), or one or more well-designed, mid-sized clinical studies of reasonably good quality (RCTs or observational studies), or several small studies aggregated into a meta-analysis (this is the CancerChoices definition; other researchers and studies may define this differently) means the practice or therapy may be linked to the outcomes described, but with a lower degree of certainty.

The evidence for these effects is described in the reviews available through the image links. A practice or therapy may show a stronger effect or have more evidence in some situations than in others.

Eating Well: good to preliminary evidence

Better fasting blood glucose and insulin among people eating legumes such as dried beans, lentils, split peas and chickpeas (good evidence)

Better blood sugar balance, insulin levels, and markers of metabolism among people eating a low-carbohydrate diet (modest evidence)

Lower insulin resistance among people with type 2 diabetes eating a diet high in inositol hexaphosphate (IP-6, abundant in cereals, legumes, and nuts) (preliminary evidence)

Lower markers of insulin resistance or metabolic syndrome among people eating foods rich in carotenoids (carrots, squash, mango, cantaloupe, sweet potatoes and tomatoes) and especially lycopene (tomatoes, guava, watermelon, papaya, red oranges, and pink grapefruit), but not after only 4 weeks (preliminary evidence)

Lower markers of blood sugar and insulin resistance among a general population drinking green tea, but not among people with prediabetes or type 2 diabetes (modest evidence)

Lower levels of insulin-like growth factor-1 (IGF-1) among people eating 8 small meals per day compared to 3 (preliminary evidence)

Higher risk of high blood sugar among people eating at night (preliminary evidence)

Moving More: good and strong evidence

Better insulin balance among people with cancer as a whole participating in physical activity (good evidence)

Some better markers of insulin balance and insulin-like growth factor (IGF) among people with breast cancer with higher levels of physical activity (strong evidence)

Better insulin balance among people with colorectal cancer with higher levels of physical activity (strong evidence)

Exercise is one of the best insulin sensitisers!

Sleeping Well: good and weak evidence

Higher risk of prediabetes or diabetes among people with either short (5–6 hours/day) or long (more than 8 hours/day) sleep durations (good evidence)

Better markers of blood sugar and insulin resistance among people with better reported sleep quality (weak evidence)

Creating a Healing Environment: good evidence

Higher risk of type 2 diabetes among people without cancer with the highest body levels of bisphenol A (BPA) (good evidence)

Manage your body weight: modest evidence

Better blood sugar and insulin sensitivity among people losing weight (modest evidence)

Berberine: good evidence

Not specific to cancer:

  • Lower markers of blood sugar among people with type 2 diabetes treated with berberine, comparable to oral oral diabetes medicine (good evidence)
  • Lower markers of blood sugar and insulin resistance among people with metabolic disorders besides type 2 diabetes treated with berberine (good evidence)
Flaxseed: modest evidence

Not specific to cancer:

  • Better blood sugar control and insulin sensitivity among people eating whole flaxseed but no evidence of a change in blood sugar control and insulin sensitivity with use of flax supplements (modest evidence)
Ketogenic diet: strong and preliminary evidence

A ketogenic diet minimizes carbohydrates and instead supplies fats as the primary energy source. The goal is to alter the metabolism of cancer cells and their associated stromal cells by decreasing glucose and increasing ketones as available energy sources.

Better blood sugar and insulin levels among people with cancer following a ketogenic diet (preliminary evidence)

Better markers of metabolism during radiation therapy among women with breast cancer following a ketogenic diet (preliminary evidence)

Not specific to cancer:

  • Better blood sugar and insulin levels among people with diabetes following a ketogenic diet (strong evidence)
Mediterranean diet: mixed evidence

Not specific to cancer:

  • Better markers of glycemic control among people with type 2 diabetes or other diagnoses following a Mediterranean diet (good evidence)
  • Lower fasting insulin and homeostatic model assessment of insulin resistance (HOMA-IR) but not HbA1C among people following a Mediterranean diet (good evidence)
  • Inconsistent evidence of an effect on fasting glucose among people following a Mediterranean diet
Metformin: mixed evidence

The FDA has approved metformin for reducing high blood sugar in people with type 2 diabetes, with substantial evidence of benefit for this condition. Use in people who don’t have type 2 diabetes is considered off-label use. Here we summarize only the evidence for metformin’s effects on blood glucose and insulin among people without type 2 diabetes or mixed groups of diabetic and nondiabetic people.

Decreases in markers of insulin-like growth factors among overweight or obese people with cancer treated with metformin (preliminary evidence)

Lower blood glucose after a meal but not while fasting among people with blood cancers without diabetes or prediabetes at baseline treated with metformin (preliminary evidence)

Good evidence of lower levels of blood sugar among nondiabetic people with breast or endometrial cancer treated with metformin

Lower levels of insulin-like growth factors among nondiabetic or mixed groups of people with breast or endometrial cancer treated with metformin (preliminary evidence)

Lower insulin levels among nondiabetic or mixed groups of people with breast or endometrial cancer treated with metformin (preliminary evidence)

Lower insulin levels among nondiabetic people with colorectal cancer treated with metformin (preliminary evidence)

Insufficient (conflicting) evidence of an effect on insulin resistance among nondiabetic people with breast, endometrial, or ovarian cancer treated with metformin

No evidence of an effect on a marker of glycemic control among men with normal glycemia and locally advanced prostate cancer treated with metformin

Not specific to cancer:

  • Lower levels of insulin, insulin resistance, or insulin-like growth factors among people without cancer or diabetes treated with metformin (preliminary evidence)
  • Lower levels of insulin, insulin resistance, and/or blood sugar among overweight or obese people, or with impaired glucose tolerance or insulin resistance, treated with metformin (preliminary evidence)
Nutrition before surgery: good evidence

Not specific to cancer:

  • Lower insulin resistance after surgery among people treated with an oral carbohydrate before surgery (good evidence)
Probiotics and prebiotics: mixed evidence

No evidence of an effect on insulin levels, blood sugar, fasting plasma glucose, insulin resistance, or insulin-like growth factor-1 among postmenopausal, overweight, and obese women with hormone receptor-positive breast cancer treated with a synbiotica combination of prebiotics and probiotics

Not specific to cancer:

  • Lower fasting blood glucose and insulin levels and a weak trend toward lower blood sugar among people with type 1 or 2 diabetes or prediabetes treated with probiotic, prebiotic, or synbiotic supplementation (good evidence)
  • Lower blood sugar and insulin resistance among adults, most of whom are diabetic or prediabetic, treated with probiotics (modest evidence)
  • Lower markers of high blood sugar and insulin levels, but no evidence of an effect on peripheral and adipose tissue insulin sensitivity, among adults treated with dietary prebiotics (not specific to cancer) (good evidence)
  • Insufficient (conflicting) evidence of an effect on fasting blood sugar, insulin resistance, or insulin among adults with metabolic syndrome or metabolic disorders treated with probiotics or synbiotics
Quercetin: mixed evidence

Not specific to cancer:

  • Lower fasting plasma glucose, although no evidence of an effect on HbA1c levels or a marker of insulin resistance, among people with metabolic syndrome and related disorders treated with quercetin (modest evidence)
  • Insufficient evidence of a lower marker of insulin resistance and no evidence of an effect on fasting blood glucose or insulin among women with polycystic ovary syndrome treated with quercetin
Tai chi or qigong: modest evidence

Not specific to cancer:

  • Better blood sugar balance among people with or at risk of metabolic syndrome (not specific to people with cancer) practicing tai chi (good evidence)
Turmeric and curcumin: modest evidence

Not specific to cancer:

  • Better blood sugar control and insulin sensitivity among people with impaired glucose tolerance or polycystic ovary syndrome treated with curcumin (modest evidence)
Vitamin D: mixed evidence

Not specific to cancer:

  • Higher risk of type 2 diabetes among people with lower 25(OH)D levels (good evidence)
  • Better markers of glycemic control (HbA1c) and lower risk of insulin resistance among people without diabetes with higher 25(OH)D levels (good evidence)Lower fasting glucose among women with polycystic ovary syndrome treated with vitamin D (modest evidence)
  • Lower insulin resistance and higher insulin sensitivity among people treated with vitamin D (modest evidence)
  • Slightly lower risk of type 2 diabetes among women with the highest vitamin D intake from supplements (modest evidence)
  • Higher insulin sensitivity and better blood glucose levels among people at risk for type 2 diabetes with higher vitamin D 25(OH)D levels (preliminary evidence)
  • Lower vitamin D 25(OH)D levels among people with diabetes (preliminary evidence)
  • Lower insulin resistance (HOMA) and better insulin sensitivity among people with diabetes or insulin resistance treated with vitamin D3 (preliminary evidence)
  • Lower insulin levels among women with polycystic ovary syndrome taking vitamin D supplements, but only when used in combination with calcium, vitamin K, zinc, or magnesium (weak evidence)
  • Weak (conflicting) evidence of an effect on glycemic control (HbA1c), fasting blood glucose, insulin levels, and other measures of blood glucose and insulin balance among people with diabetes or insulin resistance
Vitamin D and calcium together: modest evidence

Not specific to cancer:

  • Better blood sugar and insulin balance among people treated with both vitamin D and calcium (modest evidence)
Yoga: modest evidence

Not specific to cancer:

  • Better markers of blood sugar and insulin balance among people practicing yoga, mostly among people with prediabetes, diabetes, or metabolic syndrome (modest evidence)

Practices and therapies with preliminary or weak evidence of benefit for high blood sugar and insulin resistance

Preliminary evidencesignificant effects in small or poorly designed clinical studies OR conflicting results in adequate studies but a preponderance of evidence of an effect (this is the CancerChoices definition; other researchers and studies may define this differently) means the practice or therapy may be linked to the outcomes described, although substantial uncertainty remains. Weak evidenceone or more case studies, supported by animal evidence OR small treatment effects of limited clinical significance OR studies with no controls OR weak trends of effects (this is the CancerChoices definition; other researchers and studies may define this differently) may mean that the effects are small or that a high degree of uncertainty remains about the links between the practice or therapy and the outcomes described.

Combining Eating Well with Moving More Learn moreSee Less
Acupressure Learn moreSee Less
Acupuncture Learn moreSee Less
Cannabis and cannabinoids (marijuana) Learn moreSee Less
Metformin, low-glycaemic index diet, and exercise Learn moreSee Less
Non-aspirin non-steroidal anti-inflammatory drugs (NSAIDs) Learn moreSee Less
Probiotics, deep sea fish oil, glutamine, and a commercial nutrition supplement Learn moreSee Less
Quercetin and (-)-epicatechin together Learn moreSee Less
Vitamin D and omega-3 fatty acids together Learn moreSee Less
Vitamin D, vitamin K, and calcium together Learn moreSee Less

Therapies with no evidence of benefit for managing high blood sugar and insulin resistance

Reishi mushroom ›

Not specific to cancer:

  • No evidence of a clinical effect on blood sugar or insulin resistance among people with type 2 diabetes treated with reishi mushrooms in a combined analysis of 3 small studies

Vitamin D › and whey protein together

Not specific to cancer:

  • No evidence of an effect on markers of blood glucose and insulin resistance during participation in progressive resistance training among adults aged 50–75 years with overweight or obesity and with type 2 diabetes treated with whey protein and vitamin D3 in one trial

Further therapies reported to have benefit for managing high blood sugar and insulin resistance

Those in bold are evaluated favorably in a clinical practice guideline for people with diabetes; see guidelines ›

Breathing therapies

Aloe vera (oral)

Alpha-lipoic acid

Anthocyanin

A specific Ayurveda formulation of six herbs

Berberine

Bitter melon (Momordica charantia)

Citrullus colocynthis

Coccinia cordifolia

Chromium

Cinnamon

Coenzyme Q10

Fasting ›

Fenugreek (Trigonella foenum graecum)

Garlic

Ginger

Ginseng (Panex ginseng, P. quiquefolius)

Gymnema (Gymnema sylvestre)

Gynostemma pentaphyllum

Hintonia latiflora

Inositol

Ivy gourd (Coccinia indica)

Lichen genus Cladonia BAFS “Yagel-Detox”

Magnesium

Marine collagen peptides

Milk thistle

Nettle

Nuts

Omega-3 fatty acid eicosapentaenoic acid

Prickly pear cactus, or nopal (Opuntia streptacantha)

Pterocarpus marsupium (vijayasar)

Resveratrol ›

Salacia reticulata 

Scoparia dulcis porridge

Soybean-derived pinitol extract

Touchi soybean extract

Vanadium

Traditional Chinese medicine herbs:

  • Fructus Mume
  • Gegen Qinlian Decoction (GQD)
  • Jianyutangkang (JYTK) with metformin
  • Jinlida with metformin
  • Sancaijiangtang
  • Shen-Qi-Formula (SQF) with insulin
  • Tang-Min-Ling-Wan (TM81)
  • Xiaoke (contains glyburide)
  • Zishentongluo (ZSTL)

Find a physician knowledgeable about terrain factors in cancer care

Metabolic Terrain Institute of Health

These practitioners are trained regarding appropriate therapies to optimize body terrain as part of an integrative cancer care plan.

Terrain Certified Practitioner Directory

Authors

Laura Pole, RN, MSN, OCNS

Senior Clinical Consultant
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Laura Pole is senior clinical consultant for CancerChoices. Laura is an oncology clinical nurse specialist who has been providing integrative oncology clinical care, navigation, consultation, and education services for over 40 years. She is the co-creator and co-coordinator of the Integrative Oncology Navigation Training at Smith Center for Healing and the Arts in Washington, DC. Laura also manages the “Media Watch Cancer News That You Can Use” listserv for Smith Center/Commonweal. In her role as a palliative care educator and consultant, Laura has served as statewide Respecting Choices Faculty for the Virginia POST (Physician Orders for Scope of Treatment) Collaborative as well as provided statewide professional education on palliative and end-of-life care for the Virginia Association for Hospices and Palliative Care.

For CancerChoices, Laura curates content and research, networks with clinical and organizational partners, brings awareness and education of integrative oncology at professional and patient conferences and programs, and translates research into information relevant to the patient experience as well as clinical practice.

Laura sees her work with CancerChoices as a perfect alignment of all her passions, knowledge and skills in integrative oncology care. She is honored to serve you.

Laura Pole, RN, MSN, OCNS Senior Clinical Consultant

Nancy Hepp, MS

Lead Researcher and Program Manager
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Ms. Hepp is a researcher and communicator who has been writing and editing educational content on varied health topics for more than 20 years. She serves as lead researcher, program manager, and writer for CancerChoices. Her graduate work in research and cognitive psychology, her master’s degree in instructional design, and her certificate in web design have all guided her in writing and presenting information for a wide variety of audiences and uses. Nancy’s service as faculty development coordinator in the Department of Family Medicine at Wright State University also provided experience in medical research, plus insights into medical education and medical care from the professional’s perspective.

Nancy Hepp, MS Lead Researcher and Program Manager

Reviewer

Dr. Fuller-Shavel is a GMC-registered integrative medicine doctor with degrees in medicine and natural sciences from the University of Cambridge. Dr. Fuller-Shavel is a fellow of the College of Medicine and the vice chair for BSIO (British Society for Integrative Oncology). Alongside her science and medical training, Dr. Fuller-Shavel holds multiple qualifications in nutrition, integrative medicine, health coaching, herbal medicine, yoga, mindfulness and other mind-body approaches.

Dr. Fuller-Shavel is the director of Synthesis Clinic, an award-winning multidisciplinary integrative medicine practice in Hampshire, UK, specializing in women’s health, gut health (microbiome and gut-brain axis) and mental health. She combines her clinical work in women’s health and supporting patients with breast and gynecological cancer with education and training for healthcare professionals and research in precision cancer medicine and precision nutrition.

Nina Fuller-Shavel, MB, BChir, MA Hons, FBANT, IFMCP, DipIM, PG Cert RYT300

Last update: May 31, 2023

Last full literature review: July 2022

CancerChoices provides information about integrative in cancer care, a patient-centered approach combining the best of conventional care, self care and evidence-informed complementary care in an integrated plan cancer care. We review complementaryin cancer care, complementary care involves the use of therapies intended to enhance or add to standard conventional treatments; examples include supplements, mind-body approaches such as yoga or psychosocial therapy, and acupuncture therapies and self-care lifestyle actions and behaviors that may impact cancer outcomes; examples include eating health-promoting foods, limiting alcohol, increasing physical activity, and managing stress practices to help patients and professionals explore and integrate the best combination of conventionalthe cancer care offered by conventionally trained physicians and most hospitals; examples are chemotherapy, surgery, and radiotherapy and complementary therapies and practices for each person.

Our staff have no financial conflicts of interest to declare. We receive no funds from any manufacturers or retailers gaining financial profit by promoting or discouraging therapies mentioned on this site.