Thiamin Deficiency 

Thiamin, or vitamin B1, is an essential nutrient and cofactor for enzymes involved in energy production.

It plays a key role in carbohydrate and amino acid metabolism. Vitamin B1 isn’t easily stored, so it must be consumed regularly.

Without enough thiamin, a slew of symptoms may arise.

In fact, there’s been an uptick in neuropathy in recent years and thiamin deficiency is an often-overlooked possible cause. 

Diet is one cause of thiamin deficiency, however there are other contributing factors to consider. 

Today’s article addresses what you can do to optimize your thiamin levels on a Paleo diet, and answers the following questions: 

  • What is thiamin?
  • What is thiamin deficiency? 
  • What causes thiamin deficiency?
  • What thiamin-rich foods to eat on a Paleo diet? (And is it possible to eat enough thiamin in the diet without grains and beans?)
  • How can I optimize my own thiamin levels? 

What Is Thiamin? 

Thiamin, also spelled thiamine, is vitamin B1, the first essential vitamin to be discovered. Like other B vitamins, it is water soluble. 

Thiamin’s active form is called thiamin pyrophosphate, or TPP, and is a cofactor for key enzymes involved in energy production. These enzymes take glucose, amino acids and fatty acids from the food we eat and turn them into ATP, the energy currency in the body.

TPP works hand in hand with riboflavin (vitamin B2) and niacin (vitamin B3). 

Thiamin is essential, meaning we must consume it in the diet. It’s also not easily stored, so we must consume it regularly. 

The recommended daily allowance (RDA), the amount we need to eat each day, is 1.1 mg for adult women and 1.2 mg for adult men. However, needs increase during pregnancy and breastfeeding to 1.4 mg per day. 

Thiamin Deficiency

Although hard to assess, thiamin deficiency is more common than we might think.

Thiamin deficiency is associated with:

Severe deficiency of thiamin is related to Beriberi –  a disease affecting the nervous systems and multiple organ systems. 

Beriberi is categorized depending on what systems are affected: 

  • Dry beriberi includes peripheral neuropathy, also simply called neuropathy, which include symptoms of numbness, tingling or burning in the extremities due to damage to peripheral nerves. Neuropathy is a common complication of diabetes and diabetes increases the risk for thiamin deficiency and neuropathy. Dry beriberi can mimic Guillain -Barre syndrome, an acute inflammatory syndrome affecting the nervous system that is triggered by a respiratory or gastrointestinal infection.
  • Wet beriberi may include neurologic symptoms with the addition of cardiac symptoms. 
  • Cerebral beriberi may lead to Wernicke-Korsakoff syndrome, discussed below. 
  • Gastrointestinal beriberi is characterized by lactic acidosis, or the accumulation of lactic acid, which can lead to GI symptoms including abdominal pain, nausea and vomiting. 

Thiamin deficiency disorders also include Wernicke encephalopathy and Korsakoff psychosis, together known as Wernicke-Korsakoff syndrome, an acute neurologic disorder characterized by encephalopathy and changes in memory.

Development of this disorder depends upon genetic susceptibility as well as acquired thiamin deficiency. 

Wernicke’s encephalopathy affects the brain and may present as a combination of abnormal eye movements, ataxia (loss of control of muscle movements) and cognitive impairment.

When it progresses to include Korsakoff’s psychosis, also called Korsakoff’s dementia, the person appears as confused, apathetic and with significant memory loss or amnesia. 

Reasons For Thiamin Deficiency 

Thiamin deficiency may develop for several reasons including:

  • Inadequate nutrition. Not eating enough thiamin-rich foods is the most common cause of deficiency in developing countries or low-income populations. Famine and reliance on staple foods that are low in thiamin contribute. Food preparation methods may play a role as well. For example, washing milled rice decreases thiamin levels. Eating disorders are also a cause of thiamin deficiency seen in more affluent populations. 


  • Alcohol use disorders. Consuming high levels of alcohol is the primary cause of thiamin deficiency in industrialized countries. Alcohol depletes thiamin and may displace thiamin-rich foods from the diet. In addition, it contributes to reduced absorption and increased urinary excretion. Alcohol abuse is a risk factor for thiamin deficiency, beriberi and Wernicke-Korsakoff syndrome.

  • Increased need. There are times in life when we need more thiamin. These include pregnancy, breastfeeding and childhood growth. We also need more when under great physical exertion or in certain medical situations like malaria, HIV, when critically ill or undergoing surgery. Heavy alcohol use also increases needs. 

  • Increased excretion. Thiamin leaves the body via the urine and in some cases including the use of diuretics, kidney failure and alcohol abuse, thiamin excretion increases. 

  • Reduced absorption. Thiamin is absorbed in the small intestine. Malabsorption disorders, gastric surgery and alcoholism decrease thiamin absorption. 

  • Anti-thiamin factors. Anti-thiamine factors, or ATF, are components of certain foods that make thiamin inactive or un-absorbable. A diet high in ATF increases the risk for thiamin deficiency. These include:
    • Coffee, tea, decaffeinated tea
    • Certain raw fresh-water fish, raw shellfish and ferns that contain thiaminases that break down thiamin. These are inactivated by cooking. 

Treatment for thiamin deficiency is repleting thiamin levels. In many cases, people respond well, and symptoms subside. In cases of severe deficiency an IV thiamin or injection may be used. 

Paleo Food Sources of Thiamin

Conventional nutrition sends the message that we need whole grains and legumes in the diet to meet our daily thiamin needs. It is true that these foods do contain thiamin; however, a whole food Paleo diet also provides adequate dietary thiamin. 

Here are some of the best Paleo food sources: 

  • Pork
  • Fish
  • Liver and other organ meats
  • Muscles and other shellfish 
  • Pecans
  • Spinach
  • Orange
  • Melon 
  • Eggs (pasture-raised, organic)
  • Nutritional yeast
  • Seaweed
  • Sunflower seeds
  • Macadamia nuts
  • Asparagus
  • Brussels sprouts
  • Eggplant
  • Tomatoes
  • Sesame seeds
  • Squash
  • Flax seeds

How To Optimize Thiamin Levels on A Paleo Diet

In addition to including the foods mentioned above, here are some tips to make sure you are getting enough thiamin on your Paleo diet, and therefore preventing the consequences of thiamin deficiency. 

  • Take a multivitamin or B-complex as an insurance policy for thiamin and other micronutrients. 

Some options include:


Because of its water-soluble properties, supplementing with vitamin B1 is very safe and well tolerated, even at doses above the RDA.

  • Minimize or avoid alcohol. Alcohol depletes thiamin and other nutrients, puts pressure on detoxification pathways and can work against health goals. If you choose to drink alcohol, consider Dry Farm Wines for sustainable and pure natural wine. 


  • Consider annual micronutrient testing. Our micronutrient levels can change over time based on changes in the diet, changes in health, stress levels, toxin exposure and other factors. It may not be sufficient to be eating enough of a certain micronutrient, we also want to be sure your cells have enough to function optimally. The One Panel from Genova is a great option that tests thiamin as well as other vitamins, minerals and antioxidants. 


  • Optimize magnesium. Interestingly, magnesium is required to convert thiamin to its active form, TPP. Magnesium is a mineral cofactor for hundreds of biochemical reactions in the body, and a common mineral deficiency due to depleted levels in soil and eating more processed foods. 


Paleo food sources of magnesium include dark leafy greens, avocados, mineral and bone broths, nuts, seeds and sea vegetables. Most people also benefit from a magnesium supplement. (Tip: take magnesium at night to help with sleep.)


  • Consider coffee habits. A cup or two of coffee or tea per day is reasonable (if tolerated), but a pot or two may interfere with thiamin levels. Also consider that these beverages can be a source of mycotoxins and pesticides, so be sure to choose high quality, organic options. (Tip: drink from ceramic, glass or stainless containers instead of plastic to minimize microplastics and endocrine disruptors).  


  • Variety is king. When it comes to diet, it is easy to consume the same foods each day or week. Focusing on variety, however, helps to build a more robust microbiome and supports overall health. It also ensures that you are meeting your micronutrient needs. 


While a common perception is that we can’t get enough thiamin without grains and beans, the truth is it is possible by focusing on variety and eating enough protein-rich foods, organ meats, nuts, seeds and produce. Pasture raised pork and wild fish are helpful to include in your weekly menu plans as well. 

When it comes to micronutrients, thiamin often doesn’t receive a lot of attention, but is critical to energy metabolism, health and survival.

In Functional Medicine, we always consider nutrient deficiencies as a possible root cause piece for any patient’s health puzzle.

Thiamin is one to consider for neuropathy and a variety of other symptoms and diseases discussed here.