Previous studies have indicated that menaquinone-7 (MK-7) is the most effective form of vitamin K. The Japanese soya product natto is one of the richest food sources of MK-7, but its taste is not appreciated by the Western society. For this reason, the active biological compound has been manufactured as enriched oil or casein (≈80% of proteins in cow's milk)-enriched powder. However, cow's milk allergy is the most common cause of food allergy affecting a minimum of 2-3% of infants. The investigators will therefore compare this protein-delivery system to an alternative delivery system (Arabic gum; 98% polysaccharides). To compare the difference between powder and oil as MK-7 delivery vehicle, the investigators will also test the efficacy of enriched linseed oil.

Inclusion Criteria:

• Healthy men and women aged between 20 and 40 y
• Normal body weight and height (BMI <30 kg/m2)
• Stable body weight (weight gain or loss <3 kg in past 3 mo)
• Caucasian race
• Written consent to take part in the study
• Low vitamin K status

Exclusion Criteria:

• (A history of) metabolic or gastrointestinal diseases
• Chronic degenerative and/or inflammatory diseases
• Abuse of drugs and/or alcohol
• Use of corticosteroids
• Use of oral anticoagulants
• (A history of) soy allergy
• Use of vitamin K-containing multivitamins or vitamin K supplements
• Anaemia
• Blood donation or participation in another study within one month before the study