Lupin beans tick a lot of boxes in terms of nutrition. They are high in plant protein, dietary fibre and a range of micronutrients, as well as being gluten free and extremely versatile to use.
Studies suggest there are a range of health benefits from adding lupin (also known as lupini) to the diet, whether eaten whole as a snack, dried and chopped into flakes, or ground into flour.
Here, we’ll take a closer look at some of the positive attributes this legume has to offer.
The lupin bean basics
There are over 450 species of lupin. Only some species, however, can be consumed by humans, including the Lupinus albus (white lupin), Lupinus luteus (yellow lupin) and Lupinus angusifolius (blue lupin).
Being gluten-free, lupins make a useful substitute for wheat flour and can be used in a variety of bakery and pasta products, stuffings, crumb coatings, sauces, granolas and snack bars. They can also be used in alternative milk drinks or in ice-cream products.
On the down side, the beans are one of the 14 major allergens that must be clearly identified in ingredient lists under EU Regulation. The frequency of allergic reactions to lupin in the general population is unknown, but as lupin comes from the same plant family as peanuts, it may be considered a risky foodstuff for those with a peanut allergy.
Lupins have one of the highest combinations of both protein (38%) and fibre (30%) of all pulses – and indeed all plant foods. They also have a low carbohydrate content (6-10%) and contain approximately 7% fat, with the majority being unsaturated fatty acids.
There are a range of useful micronutrients found in lupin, including magnesium, potassium, zinc, iron and calcium. What’s more, the nutrients are more bioavailable due to the low levels of anti-nutritional factors, such as lectins and phytates, compared to other legumes. This also means there is no need for soaking or cooking and, unlike other legumes, sweet lupin can be eaten raw.
Lupins also contain beneficial phytonutrients, such as carotenoids, which gives lupin flour its yellow colour, and various phenolic compounds such as catechins and rutin.
Trimming the fat
Evidence suggests that using lupin-kernal fibre to replace some of the fat in a sausage patty was effective in reducing fat intake (by 37%) and calorie intake (by 17%).
Two small randomised controlled trials, meanwhile, found that lupin-enriched bread increases satiety and reduces energy intake compared with standard white bread. The increased satiety and corresponding lower intake of calories during the day from including lupins is thought to be due to their high fibre and protein content.
Helping the heart
Adding lupin fibre to the diet may also result in beneficial changes in blood lipids, which would help lower the risk of coronary heart disease. Some small randomised controlled trials of participants with high cholesterol showed that adding 25g of lupin protein per day in a protein drink or in food products resulted in reduced LDL cholesterol.
Gut health benefits
High-fibre diets are known to benefit gut health. With only 9% of adults meeting the 30g fibre a day target, fibre-rich lupins could be a useful addition to the diet.
Like other legumes, lupins act as a prebiotic in the gut, and adding lupin fibre to the diet has been shown to stimulate healthy bacterial growth. Studies have also shown that lupin fibre, when added to the diet, led to improvements in markers of a healthy bowel function which could potentially reduce the risk of colorectal cancer.
The lupin outlook
With the increasing interest in plant-based eating, vegan options, gluten-free and nutritious foods, legumes like lupin have many merits and evidence is growing regarding a range of lupin health benefits.
To top it off, lupins also tick the box in terms of being good for the environment. They require little water for growth and help improve the soil fertility by aerating it and adding nitrogen back from the atmosphere. They could therefore play an important role in sustainable agriculture.
A number of companies are already incorporating lupins into products. Plant-based protein start-up Better Nature sell organic lupin tempeh as a meat alternative, while Portuguese company Tremoceira Estrela da Piedade have had a big hit with lupin burgers.
Kraft Heinz even included a clean-label snacking product made from the legume in its Springboard incubator last year.