Is the Theory "The Further North You Go, the Healthier You Become" True?: A Discussion on Nordic Diet, Fatty Liver, and HbA1c

"The Mediterranean diet is good for health" has become common knowledge. However, now, a challenge to this "common knowledge" has arrived from the north. Fish, berries, whole grains, root vegetables, fermented milk... The **"Healthy Nordic Diet"**, constructed with ingredients typical of the Nordic region, has shown positive effects on both **type 2 diabetes (and prediabetes) and fatty liver (MASLD)**, according to research findings. Nature

The core of this topic is a 12-month randomized controlled trial (NAFLDiet trial) conducted by a group from Uppsala University in Sweden. The subjects were 150 adults with prediabetes or type 2 diabetes (of which 55% had type 2 diabetes). Participants were divided into three groups, and the primary endpoint was liver fat. As a result, the two intervention diets reduced liver fat more than "usual care," with the **Healthy Nordic Diet (HND)** showing notable positives in blood sugar and weight. Nature

First, let's understand the relationship between "MASLD" and diabetes

The fatty liver addressed in the study is increasingly being referred to as MASLD (metabolic dysfunction-associated steatotic liver disease), which is "metabolic dysfunction-associated fatty liver disease." It is a fatty liver condition not primarily caused by alcohol but is discussed in conjunction with "metabolism" issues such as obesity, lipid abnormalities, and insulin resistance. This trial also looked at how much liver fat and metabolic markers could change with diet in people with diabetes/prediabetes. Nature

The trial compared "three diets"

The NAFLDiet trial broadly compared the following three. The key point is that none of the groups were forced into "intentional calorie restriction (energy restriction)" (it was designed to be close to "eat as much as you want from the allowed foods" = ad libitum). Nature

1. Anti-lipogenic LCPUFA diet
   A concept that leans towards low-carb and reduces animal-based foods while increasing plant-derived **polyunsaturated fatty acids (PUFA)**. It focuses on sunflower oil, nuts, seeds, legumes, etc. Uppsala University

2. Healthy Nordic Diet (HND)
   A style that can be called the "Nordic version of the Mediterranean diet." It emphasizes **reducing saturated fats and increasing whole grains (oats, rye), fruits, vegetables, legumes, fish, berries, and rapeseed oil**. Uppsala University

3. Usual Care (UC)
   General dietary guidance (control group) following the Nordic Nutrition Recommendations. Uppsala University

Additionally, all three groups were asked to limit red and processed meats, sugary drinks, sweets, and sugar-added snacks. Uppsala University

So, what happened?—Key points in numbers

The key points of the research paper are as follows.

• Liver fat (primary endpoint): Both the LCPUFA diet and HND reduced liver fat more than usual care. The estimated differences were LCPUFA: -1.46% (95% CI -2.42 to -0.51) / HND: -1.76% (-2.96 to -0.57). No significant difference was observed between LCPUFA and HND. Nature

• HbA1c (blood sugar control) and weight: HND showed greater reductions in HbA1c and weight compared to other diets. Nature

• LDL cholesterol: Both HND and LCPUFA improved LDL cholesterol to a similar extent compared to usual care. Nature

• Triglycerides, inflammation, and liver enzymes: This is the "showcase of the Nordic diet." Only HND reduced triglycerides, inflammation, and liver enzymes (liver function markers). Nature

• Serious adverse events: A total of 4 cases (distributed among groups). Nature

Additionally, Uppsala University announced that among the diabetic participants, **liver fat decreased by over 20%, and more than half showed remission of fatty liver** (the announcement rephrased the content of the paper in simpler terms). Uppsala University

What's even more interesting is "why it worked." The university suggests that weight loss explains about 56% of the effect on reducing liver fat, with the rest likely contributed by the diet itself. Uppsala University

What exactly should you eat in a "Nordic diet"?

Some might associate "Nordic diet" with sausages and lots of butter. However, the HND in this study is explained by the researchers themselves as "not the traditional meat-and-butter-centric diet, but the Nordic version of the Mediterranean diet." Uppsala University

The ingredients listed as examples are quite practical. Uppsala University

• Grains: Oats, rye flakes, oat bran, rye bread, crispbread

• Oils: Rapeseed oil

• Nuts: Almonds

• Fruits: Apples, pears

• Berries: Blueberries, raspberries

• Vegetables: Cabbage, beans, (root vegetables also pair well)

• Fish: Mackerel, salmon

• Dairy: Low-fat yogurt, fermented dairy products

• And "limit": Red and processed meats, sugary drinks, sweet snacks, sugar-added snacks
  
  
  

How is it different from the Mediterranean diet?—"Oil" and "localization"

Reports emphasize that while the Nordic diet is similar to the Mediterranean diet, it is "optimized for local ingredients". While the Mediterranean diet tends to focus on olive oil, the Nordic diet promotes canola (rapeseed) oil. The Independent

This "localization" can also serve as a hint when practicing it in Japan. In other words, instead of "copying Nordic ingredients," you can transplant the concept to the Japanese dining table.

If you do it in Japan: Tips for replacing Nordic diet with "Japanese ingredients"

Not many people can get Nordic berries or rye bread every day. Therefore, by aligning with the study's philosophy (high dietary fiber, low saturated fat, fish and plant-based focus), these substitutions are practical. Uppsala University

• Staple food: Only white rice → "Mixed grains," "barley," "oatmeal," "whole grain bread," "soba (increase ratio)"

• Oil: Reduce the frequency of fried foods, and focus on "rapeseed oil" for stir-frying

• Fish: Make canned mackerel, salmon, sardines (blue fish) a "weekly regular"

• Vegetables: Bulk up with cabbage, root vegetables, mushrooms, seaweed

• Snacks: Sweet snacks → Nuts, unsweetened yogurt + fruit

• Dairy: Unsweetened yogurt, fermented milk (as much as your body tolerates)

The important thing is not "luxury in one point," but to build up as a dietary pattern. In the explanation of the Nordic diet, the idea that health indicators move with a set of food groups is repeatedly mentioned.